perf(iobufpool): optimize pool index calculations with O(1) bit manipulation#2432
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…ulation Replace O(n) loops in getPoolIdx and putPoolIdx with O(1) direct calculation using bits.Len and bits.TrailingZeros. Pool sizes are powers of 2, so we can derive indices directly from buffer size/capacity exponents. getPoolIdx: Use bits.Len to calculate ceil(log2(size)) in constant time putPoolIdx: Use bits.TrailingZeros to calculate log2(cap) in constant time Benchmarks (Apple M1 Pro): getPoolIdx: 16.97ns → 3.52ns (4.8x faster) putPoolIdx: 24.75ns → 4.16ns (5.9x faster) Get/Put cycle: 89.15ns → 76.57ns (14% faster) Get(32K): 15.38ns → 10.52ns (32% faster) Signed-off-by: Mathias Bogaert <mathias.bogaert@gmail.com>
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Replace O(n) loops in getPoolIdx and putPoolIdx with O(1) direct calculation using bits.Len and bits.TrailingZeros. Pool sizes are powers of 2, so we can derive indices directly from buffer size/capacity exponents.
getPoolIdx: Use bits.Len to calculate ceil(log2(size)) in constant time
putPoolIdx: Use bits.TrailingZeros to calculate log2(cap) in constant time
Benchmarks (Apple M1 Pro):