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Fix/min folder occupied space cache - #17996
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jt2594838 merged 2 commits intoJun 22, 2026
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…rategy MinFolderOccupiedSpaceFirstStrategy recomputed every folder's occupied space via a full Files.walk on every folder selection. While receiving a snapshot made of hundreds of thousands of tiny files, this turned each per-file allocation into a full directory-tree scan, making the cost quadratic. addPeer stalled (observed ~1 file / 4-5s) and syncLag stayed high. Cache the occupied space per folder and only recompute it periodically: an incremental selection counter is kept and, once a count threshold or a time interval is reached, the cached state is reset and the occupied space is recomputed. Selection semantics (pick the least occupied folder) are preserved while the number of full directory scans is bounded. Add a mocked unit test (DirectoryStrategyTest) and a real-filesystem integration test (MinFolderOccupiedSpaceFirstStrategyRealFsTest) covering the caching, the count-based refresh and the reset.
jt2594838
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Jun 22, 2026
MileaRobertStefan
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Jun 26, 2026
* fix(consensus): cache occupied space in MinFolderOccupiedSpaceFirstStrategy MinFolderOccupiedSpaceFirstStrategy recomputed every folder's occupied space via a full Files.walk on every folder selection. While receiving a snapshot made of hundreds of thousands of tiny files, this turned each per-file allocation into a full directory-tree scan, making the cost quadratic. addPeer stalled (observed ~1 file / 4-5s) and syncLag stayed high. Cache the occupied space per folder and only recompute it periodically: an incremental selection counter is kept and, once a count threshold or a time interval is reached, the cached state is reset and the occupied space is recomputed. Selection semantics (pick the least occupied folder) are preserved while the number of full directory scans is bounded. Add a mocked unit test (DirectoryStrategyTest) and a real-filesystem integration test (MinFolderOccupiedSpaceFirstStrategyRealFsTest) covering the caching, the count-based refresh and the reset. * fix(consensus): make occupied space cache refresh configurable
JackieTien97
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Jun 29, 2026
* fix(consensus): cache occupied space in MinFolderOccupiedSpaceFirstStrategy MinFolderOccupiedSpaceFirstStrategy recomputed every folder's occupied space via a full Files.walk on every folder selection. While receiving a snapshot made of hundreds of thousands of tiny files, this turned each per-file allocation into a full directory-tree scan, making the cost quadratic. addPeer stalled (observed ~1 file / 4-5s) and syncLag stayed high. Cache the occupied space per folder and only recompute it periodically: an incremental selection counter is kept and, once a count threshold or a time interval is reached, the cached state is reset and the occupied space is recomputed. Selection semantics (pick the least occupied folder) are preserved while the number of full directory scans is bounded. Add a mocked unit test (DirectoryStrategyTest) and a real-filesystem integration test (MinFolderOccupiedSpaceFirstStrategyRealFsTest) covering the caching, the count-based refresh and the reset. * fix(consensus): make occupied space cache refresh configurable
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Description
Cache Refresh Configuration
This PR makes the occupied-space cache refresh policy in
MinFolderOccupiedSpaceFirstStrategyconfigurable instead of hardcoding60sand1000selections.Configuration Loading
Two common config items are added with positive-value validation:
min_folder_occupied_space_cache_refresh_interval_msmin_folder_occupied_space_cache_refresh_selection_thresholdInvalid non-positive values are ignored and the defaults are kept.
Tests
Added real-filesystem coverage for the occupied-space cache behavior and updated existing strategy tests.
This PR has:
Key changed/added classes (or packages if there are too many classes) in this PR
MinFolderOccupiedSpaceFirstStrategyCommonConfigCommonDescriptoriotdb-system.properties.template