* K Prateek Nayak <kprateek.nayak@xxxxxxx> wrote:?? Mel was talking about a completely different thing, I brought up a different patch that I wanted to revert and Mel thought it would hurt other workloads which don't benefit from pulling but
Hello Libo and Peter,Mel Gorman also warned about this negative side-effect in:
tl;dr
- We observed a major regression with tbench when testing the latest tip
sched/core at:
commit 14b3f2d9ee8d "sched/fair: Disallow sync wakeup from interrupt context"
Reason for the regression are the fewer affine wakeups that leaves the
client farther away from the data it needs to consume next primed in the
waker's LLC.
Such regressions can be expected from tasks that use sockets to communicate
significant amount of data especially on system with multiple LLCs.
- Other benchmarks have a comparable behavior to the tip at previous commit
commit : 91caa5ae2424 "sched/core: Fix the bug that task won't enqueue
into core tree when update cookie"
I'll leave more details below.
Subject: Re: [PATCH] sched/fair: no sync wakeup from interrupt context
Date: Fri, 15 Jul 2022 11:07:38 +0100
Message-ID: <20220715100738.GD3493@xxxxxxx>
https://urldefense.com/v3/__https://lore.kernel.org/all/20220715100738.GD3493@xxxxxxx/__;!!ACWV5N9M2RV99hQ!PQsIeuK0UwII-A0xS-B3plepNniNeyw14OJowT1cYL-tnuN99MkWfg9C8P60tVFFrnxj0NEanUmEkA$
I've reverted this commit (14b3f2d9ee8df3b) for the time being from
tip:sched/core.
Thanks for the heads-up!
Thanks,
Ingo