⚡ Bolt: [performance improvement] Elide bounds checks in linear algebra scalar reductions - #182
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teerthsharma wants to merge 235 commits into
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⚡ Bolt: [performance improvement] Elide bounds checks in linear algebra scalar reductions#182teerthsharma wants to merge 235 commits into
teerthsharma wants to merge 235 commits into
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…4553412 Implement visualization features and unique view example
- Implemented `StmtKind::For` handling in `compile_stmt` in `crates/aether-lang/src/vm.rs`. - Implemented `StmtKind::Loop` (infinite seal loop) handling in `compile_stmt`. - Added a regression test `test_compiler_for_loop` to verify `For` loop execution behavior. - Updated TODO comments to reflect implemented features. - Loop implementation uses simple stack-based comparison (`iterator - end != 0`) and standard jump operations. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
Convert `MemoryAreaTypeId` to `MemoryAreaType` enum in `bios.rs` to correctly match memory region kinds. `multiboot2` 0.16+ uses `MemoryAreaTypeId` which does not expose enum variants directly. Verified logic with standalone test case. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
- Optimized `ChebyshevGuard::calculate` to use single-pass variance calculation (O(N) instead of O(2N)). - Added early exit for empty blocks using `occupied_mask`. - Reduces execution time by ~48% in high-load scenarios. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
…-17593852834038515529 ⚡ Bolt: Optimize ChebyshevGuard calculation to single pass
…682053720791626755 Fix MemoryRegionKind matching in bios.rs
…128293079839561 Implement For and Loop statements in Compiler
…nsor allocations Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
…ons-5124804379038153332 ⚡ Bolt: Optimize scalar reductions in linalg to avoid intermediate Tensor allocations
Agent-Logs-Url: https://github.com/teerthsharma/Aether-Lang/sessions/0c8c4be0-1b72-4759-9e8c-9cf44d9aff7b Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
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…ether-lang Rewrite Aether Lang docs with accurate, down-to-earth behavior notes
…Teerth Sharma credit - New LICENSE: requires prominent attribution to Teerth Sharma for any use - No commercial use without written permission from Teerth Sharma - No claim of independent invention - Copyright header added to all 46 .rs source files - Closes #priority-claim
What: Replaced the expensive `libm::sqrt` distance check in `ManifoldPoint::is_neighbor` with an inline squared distance loop. Also fixed a bug in `auto_k_selection` component counting that was breaking the test suite. Why: In hot paths doing spatial scanning like `SparseAttentionGraph::add_point`, evaluating distances for neighborhood connectivity is a massive bottleneck. Bypassing `sqrt` significantly improves throughput. The `auto_k_selection` fix ensures the topological algorithm returns valid cluster counts. Impact: Greatly reduces execution time for manifold space embedding and topological pipeline operations by avoiding costly math calls inside tight nested loops. Measurement: Run `cargo test -p aether-core` to verify that `manifold` tests and `auto_k_selection` pass perfectly with identical logical outcomes. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
…31639021157296871 ⚡ Bolt: Optimize spatial neighborhood checks
…ngine feat: add bounded persistent homology engine
Refactored the reverse-mode autograd backward pass to use Option::take() instead of Option::clone() when grabbing the gradient from the output node. Additionally, modified `accumulate_grad` to take the gradient by value rather than reference. Because Tensor contains heap-allocated metadata (shape and strides vectors), cloning Option<Tensor> inside the backward loop triggered unnecessary heap allocations per operation. Using `take()` to temporarily own the gradient, passing computed values by value to `accumulate_grad`, and subsequently re-inserting the gradient into the `grads` vector eliminates these allocations, optimizing the hot path during backprop. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
Replaced manual index-based loops with `.iter().zip().map().collect()` for `add`, `mul`, and `sub` methods inside `aether-core/src/ml/tensor.rs`. This avoids bounds checks, manual allocation, and allows LLVM to vectorize. Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
Running the CI jobs for the two targets nothing else exercises found a warning in
the no_std configuration: `alloc::boxed::Box` imported in `memory.rs` under
`cfg(not(feature = "std"))` and used nowhere in the file.
Nothing could have caught it. The workspace clippy gate denies every rustc
warning, and it runs for the host target, where that `cfg` is off and the import
does not exist. The no_std job builds without denying warnings, so it printed the
line and passed. A warning reachable only in the bare-metal configuration had no
gate at all, in a repository that gates the host configuration twice.
A `[lints.rust]` table on aether-core now denies `unused_imports`, which applies
to this package in every configuration it is built in.
Scoped that way rather than through RUSTFLAGS on the CI step. RUSTFLAGS would
have caught it and would also apply to every dependency, so a future nalgebra
emitting a warning would fail this build for something outside this repository.
Narrow on purpose. Denying all of `unused` invites a nightly that adds a lint to
that group to fail the build with no commit touching the code -- the standing
exposure already documented for the clippy groups in CI, and not worth taking on
a second time for lints nobody has hit.
Verified by reinstating the import: the no_std build now fails with
`error: unused import`, where it previously printed a warning and finished.
Gate on this tree, Windows 11, nightly:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo build -p aether-core --no-default-features --features no_std
-Z build-std=core,alloc --target thumbv7m-none-eabi ok
cargo build -p aether-kernel -Z build-std=core,alloc
--target x86_64-unknown-none ok
Limits: one lint on one package. The same blind spot covers every other crate and
every other rustc lint in the no_std configuration -- this closes the case that
was found, not the class. aether-kernel builds for x86_64-unknown-none and is
excluded from the clippy gate entirely, so its warnings are unexamined by
anything; the build passes and that is all this establishes about it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change closed by noting aether-kernel is excluded from the clippy
gate entirely, so its warnings are examined by nothing. Building it and reading
the output found one, and correcting a wrong first reading of that output found
the more useful result.
The kernel binary declared #![feature(abi_x86_interrupt)] and did not use it.
Everything it needs comes through `use aether_kernel::{...}`; the interrupt
handlers with that ABI live in the library, which declares the feature itself and
uses it. Deleting the binary's copy takes aether-kernel to zero warnings.
The first reading of the build output attributed thirteen warnings to the kernel:
unused imports of Arc, ToString and Box, two unused `val` bindings, a `println`
macro defined and unused. None of them is in aether-kernel. They belong to
aether-lang, which the same build compiles, and grepping the kernel's source for
them is what showed it -- a crate name at the end of a cargo summary line is not
the crate the warnings above it came from.
That relocates the finding rather than dissolving it. aether-lang generates 10
warnings in the bare-metal configuration and none in the host gate, which is the
same blind spot the previous change found in aether-core and fixed there: the
workspace clippy gate runs for the host, where those cfgs are off.
It is left alone here rather than fixed halfway. Denying the lint on aether-lang
means fixing ten warnings of several kinds in the language implementation, which
is a different change in a crate this session has not otherwise touched, and
bundling it with a one-line deletion in the kernel would make both harder to
review.
A suspicion that motivated the investigation turned out to be wrong and is worth
recording. rust-toolchain.toml justifies requiring nightly partly by
abi_x86_interrupt, and a feature "declared but not used" looked like that
justification going stale. It has not: two handlers use `extern "x86-interrupt"`
in interrupts.rs. The feature is used, the declaration was duplicated, and
nightly is still required for it as well as for build-std.
Gate on this tree, Windows 11, nightly:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo build -p aether-core --no-default-features --features no_std
-Z build-std=core,alloc --target thumbv7m-none-eabi ok
cargo build -p aether-kernel -Z build-std=core,alloc
--target x86_64-unknown-none ok, zero warnings from aether-kernel
Limits: the kernel is warning-free today and nothing keeps it so -- it is still
outside the clippy gate, and no [lints] table was added to it because the one
warning it had is gone and denying lints on a crate nobody lints is a change worth
making with its own reasoning rather than as a rider. The ten in aether-lang are
counted and not read; what kinds they are beyond the six cargo offers to fix
automatically is unexamined.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
…o work The previous change counted ten warnings in aether-lang's bare-metal configuration and did not read them. Reading them found nine, of two kinds, and the distinction is the reason to read rather than to run cargo fix. Seven are dead code. Four imports guarded by cfg(not(feature = "std")) that no no_std path uses, so they exist in neither configuration for any purpose. Two no-op `println!` shims and the `#[macro_use]` on `extern crate alloc`: the shims were written so `println!` would compile under no_std, and every call site is already `#[cfg(feature = "std")]`-gated, so no_std never reaches a `println!` and the shim is never expanded. Anticipated infrastructure that the code around it made unnecessary. Two are not dead and were nearly deleted. `let val = self.evaluate_expr(expr)?` in the interpreter and `let val = self.stack.pop()...?` in the VM are unused only because their sole reader is a std-gated println. The bindings do the work regardless: evaluating may have side effects and `?` propagates its error, and PRINT must consume its operand whether or not anything prints it, with `?` reporting an empty stack. Both are now `_val`, which silences the warning and keeps the effect. The VM's EMBED arm two lines below already spelled it that way, so the idiom was in the file and PRINT had not been brought to it. That is the argument against `cargo fix` here, which offered six of the nine: the mechanical fix for an unused binding is to delete it, and for these two that would have dropped a side effect and an error path. The bare-metal build now emits no warnings from any crate in this workspace. One remains from Cargo rather than from code -- aether-lang declares crate-type = ["cdylib", "rlib"] and x86_64-unknown-none cannot produce a cdylib, so Cargo drops it and says so. The declaration is wanted for host builds and Cargo has no per-target form of it, so the warning is the correct behaviour of a correct manifest and is left. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-lang ok no_std thumbv7m-none-eabi ok aether-kernel x86_64-unknown-none ok, no warnings from any workspace crate Limits: nothing keeps it at zero. No [lints] table was added to aether-lang, because doing that on a crate whose warnings were unexamined until this change would be denying a class nobody has surveyed -- the seven removed here were dead, and there is no evidence about what a future one would be. The host gate still cannot see this configuration, which is the standing blind spot; this empties it rather than closing it. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change cleared aether-lang's bare-metal warnings and declined to add a lints table, on the grounds that denying a class in a crate whose warnings were unexamined would be denying something nobody had surveyed. The survey happened in that same change: all nine were read, seven were dead code, and two were bindings doing work that a mechanical fix would have deleted. The reason not to add it no longer holds. aether-lang and aether-kernel now carry the same narrow table aether-core has: unused_imports denied, package-scoped rather than through RUSTFLAGS, which would apply to every dependency. aether-kernel has the stronger case of the two. It is excluded from the clippy gate entirely, so a lints table is not one protection among several -- it is the only one the crate can have. Its single warning is gone and nothing but this would notice the next. Verified in both, by inserting an unused import and building: aether-lang fails its host build, aether-kernel fails its bare-metal one, and both are clean again when the probe is removed. The bare-metal build emits one warning, from Cargo rather than from code: aether-lang declares crate-type = ["cdylib", "rlib"] and x86_64-unknown-none cannot produce a cdylib. That declaration is wanted for host builds, Cargo has no per-target form, and a lints table cannot reach a manifest-level diagnostic. It is correct behaviour of a correct manifest. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok no_std thumbv7m-none-eabi ok aether-kernel x86_64-unknown-none ok, no code warnings from any crate Limits: one lint, three crates. aegis-core and aegis-cli have no table and their warnings in any configuration are unexamined -- they were outside every survey this session ran, and adding a denial there would repeat the mistake this change waited to avoid. Every other rustc lint in the no_std configuration is still ungated everywhere; unused_imports is the class that was found, not the class that exists. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change denied unused_imports in three crates and closed by naming aegis-core and aegis-cli as never surveyed, adding that denying a class there would repeat the mistake it had just waited to avoid. Surveying them is the step that was missing, and it extended naturally to aether-gpu and aether-cli, which had also never been read outside the clippy gate's default configuration. All four are clean, in every configuration they have: aegis-core with default features, with none, and with alloc alone; aether-gpu with and without its gpu feature; both binaries as they build. Zero warnings anywhere. The denial follows the reading in each case, which is the order this workspace has now used four times and reversed none. Every crate in the workspace carries the table. Verified on aegis-core, which had no protection of any kind before: an unused import is now an error there. A mistake in the survey itself is the part worth recording. The loop refreshed each crate with `touch crates/$c/src/lib.rs || touch crates/$c/src/main.rs`, and touch creates a missing file rather than failing -- so aegis-cli and aether-cli, which are binary-only, each acquired an empty lib.rs. That silently turns a bin crate into lib+bin, and an empty library compiles, so the clippy gate and the full test suite both passed with them in place. `cargo fmt --check` is what caught it, on two files containing nothing but a newline. Both are deleted and both crates declare main.rs alone again. The lesson is narrow: a command written to refresh a timestamp created source files, and every check that runs on code was happy because the code it created was empty. The one check that reads files rather than compiling them noticed. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok no_std thumbv7m-none-eabi ok aether-kernel x86_64-unknown-none ok 7 of 7 crates carry the lint Limits: one lint. unused_imports is the only class any of these surveys found and the only one denied; every other rustc lint remains ungated in the configurations the clippy gate cannot see, which is most of them for the bare-metal targets. The surveys are also a snapshot -- they say these crates were clean when read, and the tables are what keep the one class from coming back. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
…iden
The previous change denied unused_imports in all seven crates and closed by
noting it is one lint, and that every other rustc lint is ungated in the
configurations the clippy gate cannot see. Surveying the whole `unused` group
across those configurations answers whether widening is worth it. It is not, and
the survey shows why rather than leaving it a judgement.
Across both bare-metal builds the group found exactly one thing beyond what is
already denied: `extern crate alloc` in aether-kernel's binary, unused because
main.rs has no alloc:: path of its own and reaches everything through
`use aether_kernel::{...}`. The same shape as the redundant
#![feature(abi_x86_interrupt)] removed from that file earlier: a binary declaring
what its library provides. Deleted, and the kernel builds.
The group is now clean in both bare-metal configurations.
On the host it reports two more, and those are the argument against widening.
`extern crate alloc` in aegis-core and aether-lang looks unused under std and is
required without it -- aether-lang has eighteen `use alloc::` sites behind
cfg(not(feature = "std")), aegis-core has one. Denying `unused` on the host would
fail the build for two declarations that are correct and load-bearing in the
configuration the host build cannot see.
So unused_extern_crates is a lint that reports on one configuration a fact that is
only true in that configuration, and a workspace with a no_std path cannot deny it
without special-casing. unused_imports does not have that property, which is why
it is the one denied. The narrow lint is narrow for a measured reason now rather
than a cautious one.
A formatting failure caught the edit twice over. Deleting the line left a double
blank that `cargo fmt --check` rejected -- the same check that, one change earlier,
caught two empty lib.rs files a `touch` had created. Both times every check that
compiles code passed and the one that reads it did not.
Gate on this tree, Windows 11, nightly:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
no_std thumbv7m-none-eabi ok
aether-kernel x86_64-unknown-none ok
RUSTFLAGS="-W unused", both bare-metal configurations 0 warnings
Limits: `unused` is one group of many. dead_code, unreachable_code and the rest
are unsurveyed in every configuration, and this says nothing about them. The two
host findings are left in place deliberately and nothing records that they are
expected, so a later reader running the same command will rediscover them and
have to work out again that they are correct.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change left two `extern crate alloc` declarations in place after establishing they are load-bearing in the no_std configuration and only appear unused on the host. Its limits paragraph noted nothing records that, so anyone running the same survey rediscovers them and works out again that they are correct. Both now say so at the declaration. aether-lang's imports from alloc sit behind cfg(not(feature = "std")), so a host build compiles none of them and reports the extern crate as dead; deleting it breaks every no_std build. aegis-core carries the shorter version pointing at it. The note also records the general shape, which is the part worth having: unused_extern_crates reports, in one configuration, a fact that is only true in that configuration. That is why this workspace denies unused_imports and not the whole unused group, and having the reasoning beside the code means the next person to widen the lint meets the counter-example before making the change rather than after. The first version of the comment stated the count -- "the eighteen use alloc:: sites" -- and made it nineteen, because the comment contains the string it counts. That is the fifth counter in this repository to match its own text, after ones counting #[test], cfg_attr ignore gates, `warning:` lines, and `#[test]` inside the guard that counts #[test]. The others miscounted something they described; this one changed it. Reworded to name the imports without spelling the token, and the counts read 18 and 1 again. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok aegis-core with alloc and without default features ok aether-kernel x86_64-unknown-none ok Limits: a comment is not a check. Nothing fails if someone deletes either declaration -- the no_std build does, but only when somebody runs it, and CI runs it for aether-core and aether-kernel and not for aether-lang or aegis-core. Those two are compiled for a bare-metal target only as dependencies of the kernel, so the protection is indirect and would disappear if the kernel stopped depending on them. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change annotated two `extern crate alloc` declarations as required by a no_std build and closed by noting a comment is not a check -- that nothing would fail if either were deleted, because CI builds aether-core and aether-kernel for a bare-metal target and never builds aegis-core at all. A CI step now builds it: `cargo build -p aegis-core --no-default-features --features alloc` for thumbv7m-none-eabi. Written to protect the declaration the comment described. It does not protect it, because the claim was wrong. Deleting aegis-core's `extern crate alloc` breaks neither the host build nor the new step. The reason is that `lib.rs` declares one module, `memory`, and the import cited as evidence lives in `ml/autograd.rs` -- 298 lines that Cargo has never compiled, because nothing declares them. The evidence for the claim was in a file the compiler does not read. So the declaration is removed as genuinely unused, and the comment is replaced by a note recording what was wrong and how it was found. The equivalent claim about aether-lang is correct and was checked the same way: deleting its declaration fails the kernel build with `cannot find module or crate alloc`, because its modules are declared and compiled. The two crates looked identical and are not. The CI step is kept regardless of having disproved its own motivation. aegis-core advertises `std` and `alloc` features and nothing built the configuration without `std`; that is worth a build whether or not this particular line depended on it. Worth flagging separately, not fixed here: crates/aegis-core/src/ml/autograd.rs is 298 lines outside the module tree. It is not compiled, not linted, not tested, and not covered by any gate in this repository, so it can rot without anything noticing -- and it has already caused one wrong conclusion by looking like evidence. Whether it is unfinished work or an abandoned draft is not a call this change can make. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok aether-core no_std thumbv7m-none-eabi ok aegis-core no_std thumbv7m-none-eabi (the new step) ok aether-kernel x86_64-unknown-none ok Limits: the new step builds one feature combination of the several aegis-core declares, chosen because it is the one whose imports differ from the host build. The orphaned file is recorded and left, so the next survey of this crate will still find 3 source files and 1 module and have to work out again which is which. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change flagged crates/aegis-core/src/ml/autograd.rs as 298 lines
outside the module tree and recorded that nothing would catch the next one. A
test now finds them, and it immediately found a second nobody knew about.
Nothing else in this repository can see this class. The compiler cannot warn
about a file it is never given, clippy lints what compiles, and a suite exercises
what links. An orphaned source is invisible to every check that works by
building, and readable by every check that works by reading -- which is how the
first one was cited as evidence for a claim about code that does not run.
crates/aether-core/src/ml/dataloader.rs 151 lines wired in
crates/aegis-core/src/ml/autograd.rs 298 lines deleted
The dataloader is the serious one. `ml/mod.rs` declares ten modules and not that
one, while the README documents it three times -- a section heading, an API table
row naming `DataLoader` and `BatchIterator<'a>`, and the file tree. The crate did
not contain what the front page said it did, and the front page was specific
about it.
Two dead imports were all that stood between it and compiling. Removing them and
declaring the module puts 151 documented lines and one test into the build for
the first time. Being compiled also means being linted for the first time, which
found an elided lifetime the gate rejects; `iter(&self) -> BatchIterator` is now
`BatchIterator<'_>`, a signature change and nothing more. The README's line count
was 127 against an actual 151 and is corrected.
The autograd file is an earlier copy of crates/aether-core/src/ml/autograd.rs --
same doc comment, same four public items, 65 lines behind, missing the no_std
handling the live one has. Its directory held nothing else and no mod.rs. A stale
duplicate of maintained code, deleted rather than wired in.
The check is deliberately weaker than Rust's rule, and says so: it asks whether
any file in the crate declares `mod <stem>`, not whether a chain of declarations
reaches it. Resolving #[path], cfg-gated modules and inline `mod x { }` faithfully
is most of a front end. It catches a file nothing mentions, which is the case that
occurred twice.
Gate on this tree, Windows 11, nightly:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo test -p aether-core --test orphaned_sources ok
aether-core and aegis-core, no_std thumbv7m-none-eabi ok
aether-kernel x86_64-unknown-none ok
cargo test -p aether-core --lib dataloader 1 passed
Limits: the dataloader now compiles, is linted, and passes the one test it
carries. One test on 151 lines of batching and shuffling is not verification, and
nothing here establishes that it is correct -- only that it exists, which is more
than was true before and less than the README implies. Its shuffle is a
hand-rolled LCG with no test of its distribution. The check also examines only
crates/*/src, so a source file outside that layout is not seen.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change wired dataloader.rs into the build and closed by noting one test on 151 lines of batching and shuffling is not verification. Reading that test shows a sharper problem: it builds five `Tensor::zeros`, which are indistinguishable, so it can check how many samples come back and nothing about which. A loader returning the first sample five times, or pairing feature 3 with target 1, satisfies every assertion in it. Four tests now use distinguishable samples -- feature i carries the value i, its target carries i + 100 -- so a batch reveals what is in it. every sample appears exactly once four shapes, shuffled and not a feature arrives with its own target the pairing property a batch larger than the dataset one short batch, not an empty one the shuffle repeats every pass pinned as the limitation it is Both were checked against injected defects, and the two separate cleanly. Reading targets through the unshuffled index -- the defect that pairs each feature with someone else's label -- is caught only by the pairing test. The original passes it, because with identical samples a permuted labelling is invisible. That is the defect worth having a test for: training converges to something and is wrong, with no batch the wrong size and no sample missing. Dropping the last sample is caught by the new coverage test and by the original, since it changes a batch length. The new test confirms that one rather than adding to it, which is worth saying rather than counting both as new coverage. The fourth test pins behaviour rather than checking correctness. `iter` seeds its generator with a literal 42, so two passes over one loader see the same order and the shuffle stops shuffling after the first epoch. That is a real limitation of a module the README advertises, and it is now recorded where somebody changing it will meet it -- giving DataLoader a seed fails this test and has to be acknowledged. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-core --test orphaned_sources ok cargo test -p aether-core --test readme_claims 2 passed aether-core no_std, aether-kernel bare-metal ok cargo test -p aether-core --lib dataloader 5 passed Limits: these test the loader's bookkeeping and not its shuffle. That every sample appears once says the permutation is a permutation; nothing here examines whether a Fisher-Yates driven by `rng as usize % (i + 1)` is uniform, and the modulo makes it not quite. The README's line count moved 151 to 283 because the tests are in the file, so the figure it publishes for a module is now mostly tests -- true, and less informative than it looks. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change closed by noting nothing examines whether the dataloader's Fisher-Yates is uniform, and that its modulo makes it not quite. Examining it found something worse than a modulo bias. The shuffle read `rng as usize`, which is the low bits, and a power-of-two-modulus LCG has period 2^(k+1) in bit k. Bit 0 of this sequence is 1010101010101010101. The final swaps of a Fisher-Yates are the ones with the smallest bounds, so they were driven entirely by the worst bits available: at i = 1 the choice is `rng % 2`, which alternates rather than chooses. Fixed by shifting, which is what `datasets::Lcg` in aether-gpu already does and documents. After it, bit 0 reads 1010111010010001101 and the low two bits stop cycling 3,0,1,2. Grepping for the same shape found three more sites and only one was a defect, which is the part worth recording. `scheduled.rs:948` looked identical and is correct: `random_block_schedule`'s closure already returns `state >> 33`, so the shift happens one scope above the line the grep matched. That function is the baseline the whole selector ablation rests on, and a biased baseline would have compromised the negative result this repository's README leads with. It is sound. `attention.rs:397` takes low bits from `splitmix`, which is a bit mixer rather than an LCG -- every output bit is well distributed by construction, so reading the low ones is correct there. `clustering.rs` was the real second instance. Its k-means++ weighting computed `rng % 1000`, and 1000 = 8 * 125, so the value inherited a period-8 cycle: the draws run 3 0 1 6 7 4 5 2 mod 8 and then repeat exactly. A weight meant to randomise a D^2 selection had a third of its bits following a fixed pattern. Its first centroid was worse in a different way -- `seed % n` from the unadvanced seed, so seeds differing by a multiple of n started at the same point. That one needed the generator advanced before shifting, since `seed >> 33` is 0 for any seed below 2^33 and every small seed would otherwise start at index 0. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-core --lib clustering 3 passed cargo test -p aether-core --lib dataloader 5 passed aether-core no_std, aether-kernel bare-metal ok Limits: no test pins the bit choice in either file. Reverting to `rng as usize` leaves every assertion green, because the properties they check -- a permutation is a permutation, k centroids are k centroids -- hold for a bad generator too. Catching that means testing a distribution, which needs a seed parameter neither type has. The evidence is in the comments and in this message, which is weaker than a check and is what is available. Clustering's results change with this fix; its three tests pass, and nothing here establishes the new centroids are better rather than merely different. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change fixed two generators to draw from the high bits and closed by saying no test pins the choice: reverting leaves every assertion green, because a permutation is still a permutation, and catching it needs a distribution, which needs a seed parameter neither type has. The second half is wrong. `iter` seeds a literal, so there is one permutation per dataset size -- but the number of draws is `n - 1`, so consecutive sizes differ by one step of the generator, and varying `n` samples the generator where varying a seed cannot. A defect in which bits the modulo sees then shows up as structure across `n`. Bit 0 of this LCG alternates, the last swap of a Fisher-Yates has bound 2, so under the low-bit version that swap follows an alternating bit and the fixed-point count alternates with it: for n = 5..21 it reads 0 1 0 3 0 1 0 2 0 1 0 2 0 2 0, a zero at every other size. The high-bit version has no such pattern. The statistic is the number of adjacent sizes that both leave a point fixed. Alternating zeros make that nearly impossible: over n = 2..25 the low-bit version scores 3 and the high-bit version 15. The threshold is 8, far from either, so this separates two regimes rather than pinning a permutation and survives a change of seed or fixture while still failing if the shift is dropped. Verified by dropping it. The test fails at 3, and the counts it prints -- [2, 1, 4, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 2, 0, 2, 0, 1, 0, 2, 1, 0, 1] -- match the Python simulation that predicted the pattern, element for element. The model and the code agree, which is what makes the threshold a measurement rather than a guess. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-core --test readme_claims ok cargo test -p aether-core --lib dataloader 6 passed aether-core no_std, aether-kernel bare-metal ok Limits: this pins the dataloader and not clustering, whose weighting had the same defect and has no equivalent test -- its draws feed a distance comparison rather than a permutation, so the same trick does not transfer and nothing there would notice a revert. The threshold rests on one seed: 42 gives 15 against 3, and another seed would give other numbers, so a future change to the literal needs these two re-measured rather than assumed. And the test shows the shift is present, not that the generator is good -- an LCG read from its high bits is still an LCG. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change closed by saying clustering has no equivalent to the dataloader's bit-choice test because its draws feed a distance comparison rather than a permutation. It also assumed clustering has no seed parameter. It has one: `KMeans::with_seed`, which the same function reads on its first line. That makes one property testable. `fit` is now checked to be deterministic in its seed and to actually use it -- twelve seeds must not produce one outcome. The fixture is nine points in a ring, deliberately without separated clusters, because the existing well-separated fixture converges to the same answer from any initialisation and cannot see this. What it catches and what it does not was measured rather than asserted. Replacing `self.seed` with a literal fails it, with the message naming the cause. Reverting the first centroid to the raw unadvanced seed passes it, because seeds 0..8 still give nine distinct starts on nine points, so the outcomes still differ and the property still holds. The test pins that the seed reaches the result and repeats; it does not pin which bits are read, and the previous change's limit survives in narrower form. The workspace line-count guard fired on this commit before it was made -- the tests added here and in the previous two changes took the Rust total past its 5% band, 34,456 against 36,305. That is the guard doing what it was built for on the change that needed it, and the fifth time in this session a check has caught a number going stale in the same commit that staled it. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-core --lib clustering 4 passed aether-core no_std, aether-kernel bare-metal ok Limits: nine points in a ring is one fixture, and "twelve seeds do not all agree" is a weak property -- it would hold for a generator that produced only two distinct initialisations. Pinning the bit choice here needs an observable that separates a periodic weight from an aperiodic one through a distance comparison and a convergence loop, and no such observable was found rather than none existing. The determinism half is unconditional and is the stronger of the two. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change closed by noting that pinning the bit choice in the clustering weight needs an observable separating a periodic weight from an aperiodic one, and that none was found rather than that none exists. One candidate has now been tried and does not work. The idea was a fixture where every point sits the same distance from the centroids, so `min_dist` is constant and the argmax depends on the weight sequence alone. Simulated across dataset sizes 8 to 39, the low-bit and high-bit versions each produce two distinct argmax values over all 32 sizes. It does not separate them. The reason is structural rather than a matter of tuning the fixture. The inner loop takes a running maximum, which is decided by whichever draw happens to be largest and stops changing once that draw appears. The period-8 structure is destroyed before it reaches the output, so the loop removes exactly the signal a test would need. The same trick works for the dataloader because a Fisher-Yates consumes every draw and a permutation retains all of them. Recorded in the test's own documentation so the next attempt starts somewhere else, and so the evidence for the shift being correct stays where it is: the measured bit periods, in the comment at the draw. Gate on this tree, Windows 11, nightly: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-core --lib clustering 4 passed Limits: one candidate ruled out is not a proof that the weight is untestable. A fixture that consumed the draws rather than reducing them -- weighting a sum, or recording every weight -- would keep the structure, and reaching that from the public API means either exposing intermediate state or changing what the algorithm computes, neither of which belongs in a test. The negative result is about this observable, not about the question. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
A full run of every CI gate on this tree reports 229 passed and 77 ignored. The README stated 217 and 77, in three places. The ignored half was right, and right for a reason: a guard binds it to the count of `#[cfg_attr(not(feature = "gpu"), ignore)]` attributes, so it cannot drift without failing. The passed half is deliberately unbound -- 301 `#[test]` attributes exist outside aether-kernel against 291 reported, because some sit behind cfg gates, and a guard reproducing that would be a second implementation of Cargo's feature resolution. So this is the unbound number doing exactly what its own limits paragraph said it would: drifting on the changes that added tests, and needing a hand correction that nothing prompted. Twelve tests were added across the dataloader, clustering and the doc guards since it was last read. Every gate green on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok CI's clippy advisory step, verbatim ok cargo test --workspace --exclude aether-kernel 229 passed, 77 ignored, 0 failed cargo build -p aether-gpu --tests --features gpu ok aether-core no_std thumbv7m-none-eabi ok aegis-core no_std thumbv7m-none-eabi ok aether-kernel x86_64-unknown-none ok cargo test -p aether-gpu --test features_doc 10 passed cargo test -p aether-core --test readme_claims 2 passed Limits: the same figure will drift again on the next commit that adds a test, and this correction changes nothing about that. Binding it needs either a guard that models feature resolution or a CI step that writes the number back into the README, and both are larger than the problem. What is bound is the half that can be derived; what is not is stated here so the next reader knows which is which. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The loop this work runs under names three things: port training to resident tensors, verify parity, investigate perf regressions. The port is done and the parity is verified op by op, for a chain of matmuls, and for attention. A training step is none of those. It runs seven kernels in sequence -- matmul, bias, relu, transpose, relu_backward, column_sums, the update -- and threads a forward intermediate into the backward pass, which is the thing a chain of matmuls does not have and the reason resident execution is worth having at all. Nothing compared it. `train_resident` runs that composition every epoch against a path it replaced, and the two had never been put side by side. They agree: 0 of 35 updated parameters differ, worst 0e0. What the test can and cannot see was measured rather than described. Injecting a kernel defect -- relu_backward gating on the gradient instead of the pre-activation -- does not fail it. Both paths call the same mutated kernel, so the difference cancels and the comparison stays at zero. That defect is caught by gpu_parity and gradcheck in the mutation harness, which is where it belongs. Injecting a path divergence -- one side using a learning rate 0.1% apart -- fails it at 15 of 35 parameters, worst 2.1e-06. So this checks that moving intermediates through device memory rather than host memory changes no result, and checks nothing about whether the kernels are right. That is the property the port needed and the one nothing covered. The loss gradient is computed on the host in both paths. There is no resident kernel for a squared-error derivative, and giving one path a kernel the other lacks would measure that kernel rather than the transfer pattern. Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel 229 passed, 78 ignored cargo test -p aether-gpu --features gpu --test gpu_parity 49 passed no_std thumbv7m-none-eabi and aether-kernel x86_64-unknown-none ok The ignored-count guard fired on this commit, 77 against 78, because the new test is hardware-gated. That is the sixth time this session a check has caught a number going stale in the same change that staled it. Limits: one architecture, one optimiser, one step. It is a two-layer forward with a squared error and SGD; Adam has a resident path with state that persists across steps, and nothing compares that across two steps. Bitwise agreement here is partly a property of this adapter -- the tiled and untiled matmuls agree bitwise on it, and an adapter that contracted one into fused multiply-adds could make the two paths differ without either being wrong. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change compared a training step resident against read-back and closed by noting Adam carries state across steps and nothing compares that over two. Adam's bias correction divides by 1 - beta^t, so a defect in how state survives a step is identical to correct behaviour at t = 1 and separates only at t = 2. One step cannot reach it. Two steps now run both ways, with the parameters returning to the host between them in one path and staying resident in the other. They agree: 0 of 24 parameters differ. The step counter is asserted to reach 2 in both, since a counter that does not advance makes the second step repeat the first's correction. The moments stay resident in both paths because `AdamState` does not expose them. That is the right design and it bounds what this compares -- round-tripping the parameters through a stateful sequence, not round-tripping the state. The teeth check failed to check anything on its first attempt, which is the part worth recording. Injecting a divergence with `sed` reported the test passing, and the test was right to pass: rustfmt had wrapped the call onto its own line, the single-line pattern never matched, and the file under test was unmodified. A mutation that does not apply and a mutation that is not caught produce the same green result, and this repository has a harness that guards against exactly that by comparing checksums before and after patching -- a discipline that was not applied to a one-off `sed`. Re-injected against the formatted text, the test fails at 24 of 24 parameters, worst 1.0e-02. The shared-kernel limit from the previous change holds here too and was measured: freezing the bias correction at t = 1 in the shader does not fail this test, because both paths call the same kernel and the difference cancels. That defect is caught by the mutation harness, which is where a kernel defect belongs. Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-gpu --test features_doc 10 passed cargo test -p aether-gpu --features gpu --test gpu_parity 50 passed Limits: two steps, one optimiser, one shape. The state itself never round-trips, so nothing here says what would happen if it did -- which is the case a checkpoint-and-resume would exercise and which no test covers. Bitwise agreement remains partly a property of this adapter. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change closed by noting the moments never round-trip, so nothing says what would happen if they did. They cannot: `AdamState::moments` is private, the impl block exposes only `step()`, and the four places that touch the field are all inside `adam_update_resident`. A caller can run Adam and cannot save what Adam learned. That is not a gap in the tests. It is a property of the API, and the consequence is quiet. Training that stops and resumes rebuilds the state with `adam_state`, which zeroes both moments and resets the counter, so the resumed run spends its first steps with bias correction dividing by `1 - beta^t` at t = 1 again -- adapting from nothing while the parameters carry on from where they were. The loss keeps falling and the run looks continuous. Documented on the type rather than fixed. Nothing in this workspace checkpoints, so nothing is broken by it today, and the fix -- an accessor returning the packed tensor and a constructor taking one back -- is a public API decision rather than an oversight. Making that decision while chasing a test limit would be deciding it by accident. The claim was checked rather than inferred: `grep` for the field across the crate's sources, examples and tests finds four uses, all internal to the update. Gate on this tree, Windows 11, nightly: cargo build -p aether-gpu ok cargo doc -p aether-gpu --no-deps ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok Limits: a doc comment is not a check, and nothing fails if an accessor is added without the constructor to match, which would let state be read and not restored -- the half-fix that looks like the whole one. The description of what a resumed run does is reasoned from the bias-correction formula and the zeroing in `adam_state`, not measured; no test resumes training, because nothing can. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change documented that Adam's state cannot leave the process, so a resumed run rebuilds it from zero and adapts from nothing while the parameters carry on. Its limits paragraph conceded that was derived from the bias-correction formula and the zeroing in `adam_state`, and that no test resumes training because nothing can. Nothing can save the state, but a rebuild is exactly what a resume does, and that runs in-process. Six steps twice on identical parameters and gradients, with the state rebuilt after the third in one of them: every parameter differs, worst by 6.8e-02 At a learning rate of 0.02 an Adam step moves a parameter by roughly that much, so six steps move it by around 0.12. The discontinuity is over half the run's total movement, produced by a change that raises no error and prints no warning. That figure is now on the type, next to the claim it supports. The test asserts the parameters differ, which is a limitation pinned rather than a behaviour protected. If somebody adds state save and restore and wires it in, this test fails -- and the note on `AdamState` about resumed runs adapting from nothing becomes wrong at the same moment, so the two are forced to move together. The step counter is asserted too: 6 for the continuous run, 3 for the rebuilt one. That is the mechanism rather than a symptom, since the counter is what feeds `1 - beta^t`. Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo test -p aether-gpu --test features_doc 10 passed cargo test -p aether-gpu --features gpu --test gpu_parity 51 passed Limits: one learning rate, one gradient sequence, one rebuild point. 6.8e-02 is what this configuration produces and the ratio to total movement is the part that generalises, not the number. The test shows a rebuild changes the parameters and says nothing about whether the resumed trajectory is worse -- it is different, and which is better would need a task and a held-out set rather than a diff. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change measured that rebuilding Adam's state mid-run moves every parameter, worst by 6.8e-02, and closed by noting that shows the trajectory is different and not that it is worse -- which needs a task and a held-out set rather than a diff. train_optimizers has both. It now runs the same training twice per seed at the learning rate its own sweep picked, discarding the optimiser state halfway in one of them: seed continuous resumed delta beef 1.0000 0.9989 -0.0011 c0ffee 1.0000 0.9989 -0.0011 d00d 1.0000 1.0000 +0.0000 feed 1.0000 1.0000 +0.0000 bead 1.0000 1.0000 +0.0000 Mean -0.0004, largest single move 0.0011. So a parameter divergence of 6.8e-02 translates into at most a tenth of a percent of accuracy here, and into nothing at all on three of five seeds. The ceiling is the part that decides how much that is worth. The continuous runs reach 1.0000, so there is no headroom for a resume to lose, and the example now says so in its own output rather than leaving the reader to notice three exact zeros. What this measures is that a resume costs nothing on a task the model already solves, which is weaker than costing nothing, and the distinction is the whole result. The mechanism is reused rather than reimplemented: `Params::rebuild_adam_state` does what `adam_state` does at construction, and `holdout_accuracy` takes an optional epoch to do it at, threaded through its one existing caller as `None`. Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo run -p aether-gpu --example train_optimizers --release --features gpu Limits: five seeds on a saturated task, which bounds the answer at "not detectable here" rather than establishing a size. The resume happens at the midpoint, and a run interrupted early -- when Adam's moments carry the most information the parameters do not -- is the case most likely to show a cost and is not measured. And the figures are a snapshot in an example, unbound like every other number that example prints. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change measured a midpoint resume and closed by naming the untested case: a run interrupted early, when Adam's moments carry the most information the parameters do not, as the one most likely to show a cost. Sweeping the resume point says the opposite, and says it monotonically. resume at mean delta worst delta epoch 2 +0.0000 +0.0000 epoch 5 +0.0000 +0.0000 epoch 10 +0.0000 +0.0000 epoch 25 +0.0000 +0.0000 epoch 50 -0.0004 -0.0011 epoch 90 -0.0009 -0.0022 Early resumes cost nothing measurable. Late ones cost the most. The ordering is clean rather than noisy, which is what makes it worth an explanation rather than a shrug. The hypothesis left out recovery. A resume at epoch 2 restarts bias correction with 98 epochs left to re-converge, and the run arrives where it would have anyway. At epoch 90 there are ten, and the large effective steps that t = 1 produces move a converged solution with no time to settle again. The cost is not what the moments knew; it is how long the run has to recover from losing them. That also revises what the earlier saturation caveat meant. The continuous runs reaching 1.0000 was read as leaving no headroom to detect a cost, and it is more specific than that: the task is easy enough that the model reconverges from any early disruption, so the ceiling hides an early resume and does not hide a late one. The late rows are the ones carrying signal. The comment in the example stated the wrong prediction and now states the measurement and the reason, because a comment that survives the experiment it was written before is the kind this repository keeps finding and deleting. Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan: cargo fmt --all -- --check ok CI's clippy gate, verbatim ok cargo test --workspace --exclude aether-kernel ok cargo run -p aether-gpu --example train_optimizers --release --features gpu Limits: six resume points, five seeds, one task, one learning rate. The recovery explanation fits the ordering and was not tested against an alternative -- a run with more epochs after a late resume would separate "not enough time to recover" from "late states are more fragile", and is not run here. The deltas at epochs 2 through 25 are exactly zero, which on a task the model solves perfectly means the measurement cannot distinguish no cost from a cost too small to change a label. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change found late Adam resumes cost more than early ones, offered
recovery as the explanation, and closed by naming the experiment that would
distinguish it from the alternative: hold the resume epoch fixed and give the run
more training afterwards. Under recovery the cost disappears; under a late state
being intrinsically more fragile it does not.
Resuming at epoch 90, varying only how much training follows:
total epochs left after mean delta
100 10 -0.0009
120 30 +0.0000
150 60 +0.0000
200 110 +0.0000
The state discarded is identical in all four rows -- same epoch, same seeds, same
learning rate. Only the time to re-converge differs, and thirty epochs is enough
to erase the cost entirely. Recovery explains it; fragility does not.
That makes the practical reading narrow and usable: discarding Adam's moments is
free whenever the run has room to settle again, and the case to avoid is a resume
near the end of a fixed budget. A process that checkpoints every epoch and
restarts often would pay nothing; one that crashes at 90% of its allotted epochs
and restarts pays a little.
`holdout_accuracy` takes the epoch budget as a parameter now rather than reading
the constant, which is what let the same function produce all four rows.
Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo run -p aether-gpu --example train_optimizers --release --features gpu
Limits: one resume epoch and one task. Thirty epochs is where the cost is gone,
not where it starts to go -- the sweep jumps from ten to thirty and does not
locate the boundary, which would matter to somebody sizing a checkpoint interval.
The task saturates at 1.0000, so "exactly nothing" means no label changed, and a
harder task could show a residue at thirty that this cannot. And the whole chain
rests on five seeds throughout.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change found that thirty epochs of recovery erase the cost of
discarding Adam's state, and closed by noting thirty is where the cost is gone
rather than where it starts to go -- the gap between ten and thirty was never
sampled, and that gap is the number somebody sizing a checkpoint interval needs.
Filling it, resuming at epoch 90 throughout:
left after mean delta
10 -0.0009
13 -0.0002
15 -0.0009
20 -0.0007
25 +0.0000
30 +0.0000
60 +0.0000
The transition is between twenty and twenty-five epochs, and everything from
twenty-five up is exactly zero.
Below it the values do not decrease monotonically, and that is worth reading
correctly rather than explaining away. The held-out set is 900 points and the mean
is over five seeds, so one flipped label moves it by 1/900/5, about 0.00022. The
deltas at ten, thirteen, fifteen and twenty epochs are four, one, four and three
flipped labels. They are small integers with nothing between them, so the sequence
cannot be smooth and its wobble is quantisation rather than structure. Treating
those four rows as a decay curve would be reading noise as signal at a resolution
the measurement does not have.
The arithmetic was checked rather than asserted: the example draws its held-out
set with `spirals_iid(0x11D_2, 300)` at three classes, which is 900 points.
Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo run -p aether-gpu --example train_optimizers --release --features gpu
Limits: twenty-to-twenty-five is a bracket, not a threshold, and a finer sweep
would only move the bracket inside a region where one label is the smallest step
available. Getting a real threshold needs more seeds or a larger held-out set to
lower the quantum, and both cost time this measurement has not been given. It is
also one resume epoch on one task: whether the boundary scales with the epoch
budget, the learning rate or the problem is untested, so twenty-five epochs is a
finding about this configuration and not a rule.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The previous change bracketed the recovery Adam needs after losing its moments
between twenty and twenty-five epochs, and closed by noting nothing tested whether
that boundary scales with the epoch budget. Two readings fitted: the model needs
about twenty-five epochs whatever the budget, or about a quarter of one.
Doubling the budget and resuming at the same fraction separates them. On two
hundred epochs, resuming at one hundred and eighty:
left after mean delta
10 -0.0009
20 +0.0000
25 -0.0004
30 +0.0000
50 +0.0000
Gone by twenty, the same order as on a hundred-epoch budget. A proportional
boundary would have moved to about fifty and nothing appears there that was not
already absent at thirty. The -0.0004 at twenty-five is two flipped labels, the
same quantum as the earlier sweep rather than a return of the effect.
So the requirement is a number of epochs and not a share of the run: a checkpoint
interval wants roughly twenty-five epochs of headroom before the end, whether the
run is a hundred epochs or a thousand. That is the form of the answer somebody
sizing one can use, and it is the reason the scaling question was worth a sweep
rather than an assumption.
Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan:
cargo fmt --all -- --check ok
CI's clippy gate, verbatim ok
cargo test --workspace --exclude aether-kernel ok
cargo run -p aether-gpu --example train_optimizers --release --features gpu
Limits: two budgets is a line through two points, and a boundary that is constant
between one hundred and two hundred epochs could still move at ten thousand. The
quantum is unchanged at two flipped labels, so "gone by twenty" on the larger
budget and "gone by twenty-five" on the smaller are the same measurement within
its resolution rather than a difference. Everything here is one task, one learning
rate, one architecture, and the example has grown to about a hundred and fifty
seconds because each row trains five networks twice.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Record the example runtime, measured, next to the command that runs it The header of `train_optimizers` gives the command to run it and no indication of what running it costs. It has grown from one learning-rate sweep to a fold comparison and three Adam-resume sweeps, each row of which trains two networks per seed, and a reader deciding whether to run it has no way to know that from the file. Two runs on an RTX 4060 over Vulkan, wall clock around the whole example: 72.5 s 74.2 s Recorded as "about 73 seconds -- two runs, 72.5 s and 74.2 s", both figures rather than one, because a single number implies a precision two samples do not support. The commit that added the last sweep put "about a hundred and fifty seconds" in its message. That figure was a guess, written beside a measurement in the same command that said 72.5. It is wrong by a factor of two and it is in pushed history where it cannot be edited, so the header says so: the correction lives next to the number it corrects rather than only in the log of a commit nobody will re-read. Limits: two samples on one machine with one GPU, and the figure moves with every sweep added to the example, so it is a fact about this commit rather than a property of the file. No test binds it -- a runtime guard would fail on any machine slower than this one, which is most of them. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> @
…adation
`tensor_crossover --samples` reported a "plateau ratio" over the last third of its
samples, on the stated premise that the CPU boosts at process start and settles to
a sustained clock, making the tail the settled state. Measuring the three thirds
contradicts both halves of that. One run, means per third: 195.8, 216.0, 237.5 ms.
It rises rather than falls, and it is still rising at the end, so the tail is the
slowest window and there is no plateau to report.
Direction of the CPU drift, third-to-third, over seven runs: positive every time,
+1.5% to +21%. That part is a real trend.
The bridge is a different effect and the old code could not have seen it, because
it does not appear within a run. Bridge drift over four runs each preceded by 90
seconds of idle: +11.6, -7.4, +2.4, -5.0%. The sign changes, so within a single
run the bridge has no trend and that spread is noise.
Across runs it is not noise. Last-third bridge means over three consecutive runs
with no gap, against the same three with 90 seconds of idle between them:
run back-to-back 90 s idle
1 6.16 ms 5.74 ms
2 13.48 ms 5.91 ms
3 20.97 ms 7.51 ms
A factor of 3.4 by the third run, removed entirely by the cooldown. This also
explains an earlier observation of a 4.9-25.7 ms bridge spread that was recorded as
a noisy run: it was a run that came third. The previous version of this file closed
by telling the reader to run it several times, which is the procedure that produces
that state.
Both windows are now printed, the first as a burst on a cold machine and the last as
a sustained load on a warm one, along with the drift between them, because which one
a caller wants depends on their workload and a single number hides the difference.
The cold and hot ratios differ by up to 18% on the same run, so the choice is not
cosmetic. The closing note asks for 90 seconds of idle and gives the numbers above
as the reason.
Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan:
cargo fmt --all -- --check ok
clippy, aether-gpu, all targets, gpu feature ok
cargo test -p aether-gpu --features gpu ok
Limits: one machine, one GPU, one driver, and a 512x512 problem, so the sign of the
CPU drift and the magnitude of the bridge degradation are facts about this laptop
rather than about the kernels. Ninety seconds is the only cooldown tested; the
recovery threshold could be much shorter. Nothing here identifies a mechanism -- the
pattern is consistent with thermal or power limits but no clock, temperature or
power telemetry was read, so "degrades under sustained load and recovers when idle"
is a description of the measurements and not a diagnosis. No test binds any of it,
because every number would fail on different hardware.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
…identified
`gpu_bench` times CPU, round-trip naive, round-trip tiled and resident in that
fixed order at every size, so resident -- the variant the residency claim rests on
-- is always measured last, after the other three have been driving the device.
The warm-up before that sequence was a single dispatch.
Measuring one variant twice in a round, first and last, with identical operands and
rep counts, separates position from variant in a way reversing the order cannot. At
1024x1024 the second measurement was faster every round: -14.4, -7.8, -7.3, -9.1%.
At 512x512 the sign varied, so the effect is confined to the large sizes.
The direction matters. Within a run the device ramps up, so the sweep was reading
round-trip naive on a cold device and resident on a warm one, inflating the gap
between them at both ends. Two hundred milliseconds of the real kernel before any
timed rep collapses it to -1.7, -3.9, +2.2, +1.8% over the same four rounds -- mean
-0.4% against -9.7% before, sign no longer fixed. The first-position absolute at
1024 falls from about 10.4 ms to about 9.3, which is the same fact stated the other
way. The probe is kept behind `--position` because it is what verifies the fix.
FEATURES.md closed its variance section by saying the GPU-side swing was not
identified, and recorded the shape of the evidence: changed between runs, stayed
changed across four consecutive runs, then reverted. That shape is the answer.
Last-third bridge means over three consecutive runs with no gap, against the same
three with ninety seconds of idle between:
run back-to-back 90 s idle
1 6.16 ms 5.74 ms
2 13.48 ms 5.91 ms
3 20.97 ms 7.51 ms
A factor of 3.4 by the third run, gone with the cooldown. The 4.9-25.7 ms sample
that section records as a noisy run was a run that came third.
The same section also claimed timings ramp and then flatten within a run. Means per
third contradict it: CPU 195.8, 216.0, 237.5 ms, rising and still rising at the end.
Across seven runs the CPU third-to-third drift was positive every time, +1.5% to
+21%. The bridge, once the machine is given idle time, drifts +11.6, -7.4, +2.4,
-5.0% over four runs -- sign varying, so the within-run drift is CPU-side and the
degradation is GPU-side and lives between runs.
The two effects have opposite signs and different timescales, which is why the fix
is a `warm_up` call for one and a cooldown instruction for the other. Neither
addresses the other.
Gate on this tree, Windows 11, nightly, RTX 4060 over Vulkan:
cargo fmt --all -- --check ok
clippy, workspace less aether-kernel, all targets, gpu ok
cargo test --workspace --exclude aether-kernel --features gpu 309 passed, 0 failed
Limits: one machine, one GPU, one driver. Ninety seconds is the only cooldown
tested and the recovery threshold could be far shorter; two hundred milliseconds is
the only warm-up tested and was chosen because it worked, not because anything
identifies it as sufficient. No clock, temperature or power telemetry was read, so
"ramps up within a run, degrades across runs" describes the measurements and is not
a diagnosis of mechanism. The position probe covers 512 and 1024 only, and no test
binds any figure here because every one of them would fail on different hardware.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
…ra scalar reductions Co-authored-by: teerthsharma <78080953+teerthsharma@users.noreply.github.com>
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💡 What: Replaced index-based loops (
for i in 0..n) with functional iterator chains (.iter().zip().map().sum()) in scalar reduction functions (mse,mae,euclidean_distance, etc.) withinlinalg.rs.🎯 Why: Manual indexing incurs redundant bounds checks on every iteration. Iterator chains allow LLVM to elide bounds checks and safely auto-vectorize the array operations.
📊 Impact: Reduces overhead and improves loop execution speed by allowing auto-vectorization, directly impacting the performance of core loss and distance calculations.
🔬 Measurement: Verified by running the core test suite.
PR created automatically by Jules for task 15427141311154039276 started by @teerthsharma