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0 pointstux33y ago0 comments

I don't know how sophisticates the streaming/prefetch/access pattern prediction the 2002 cpus did was.

I'm speculating, but if that's not modeled, cachegrind may pessimize some less simple predictable patterns and report a lot of expected misses when the cpu would have been able to prefetch it

0 comments

andrewf3y ago

Agreed, I suspect it'd be most accurate to say the SQLite folks are minimizing their working set.

I picked a couple of random performance commits out of their code repo, and they look like they might keep 1 or 2 lines out of i-cache: https://sqlite.org/src/info/f48bd8f85d86fd93 https://sqlite.org/src/info/390717e68800af9b

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0 pointstux33y ago0 comments

I don't know how sophisticates the streaming/prefetch/access pattern prediction the 2002 cpus did was.

I'm speculating, but if that's not modeled, cachegrind may pessimize some less simple predictable patterns and report a lot of expected misses when the cpu would have been able to prefetch it

0 comments

andrewf3y ago

Agreed, I suspect it'd be most accurate to say the SQLite folks are minimizing their working set.

j / k navigate · click thread line to collapse