Embedded strings memory reduction #7
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AvivDavid23
commented
Aug 13, 2025
AvivDavid23
commented
- Reduce the Header size of strings
- Allow storing strings with length <=7 on the pointer values itself, reducing allocations
| // Set the length in the first byte (after tag bits) | ||
| data_bytes[0] = (s.len() << TAG_SIZE_BITS) as u8; | ||
| data_bytes[1..1 + bytes.len()].copy_from_slice(bytes); | ||
| let data: usize = usize::from_ne_bytes(data_bytes); |
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Excellent choice to use from_xx_bytes. We can accept using native endianness because strings are never written in this form.
| /// Safety: Must be called on inline string(strings are valid UTF-8) | ||
| unsafe fn extract_inline_str(&self) -> &str { | ||
| let data_ptr = &self.0 as *const IValue as *const u8; | ||
| let bytes: &[u8; 8] = transmute(data_ptr); |
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Let's match it with the equivalent to_xx_bytes here to ensure endianness never plays any role in de/serialization.
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I don't think there is a to_ne_bytes fn which I can use here
ephraimfeldblum
approved these changes
Aug 21, 2025
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