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AndresFreundTec /
npub1ly4…ks2j
2024-08-10 03:32:11

AndresFreundTec on Nostr: Uh. Huh. Is it expected that SMAP can lead to a noticeable reduction in speed of ...

Uh. Huh. Is it expected that SMAP can lead to a noticeable reduction in speed of copying from kernel to userspace?

It seems to be tied to CPU caches to some degree.

Reading a large, cached, file from the kernel I get substantially higher throughput when aggressively reusing the "target" buffers. But there's very little difference if I boot with clearcpuid=smap.
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