Change uint32_t fields to uint16_t to reduce FreeList footprint. - #1086
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This eliminates internal padding when the FreeList structure inherits from LinkedList. The FreeList structure requires 12 bytes of fields, and replacing them with uint16_t allows all fields to fit within 6 bytes, allowing the complete FreeList sizes to fit into exactly 16 bytes rather than 24 or 32 bytes (depending on standard layout trailing padding). This saves at least 16 bytes per size class for 93 size classes, yielding ~1.5 KiB memory saved per thread, or ~150 KiB for a typical 100-thread process. PiperOrigin-RevId: 987041263
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Change uint32_t fields to uint16_t to reduce FreeList footprint.
This eliminates internal padding when the FreeList structure inherits from LinkedList.
The FreeList structure requires 12 bytes of fields, and replacing them with uint16_t allows all fields to fit within 6 bytes, allowing the complete FreeList sizes to fit into exactly 16 bytes rather than 24 or 32 bytes (depending on standard layout trailing padding).
This saves at least 16 bytes per size class for 93 size classes, yielding ~1.5 KiB memory saved per thread, or ~150 KiB for a typical 100-thread process.