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charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable On 8/21/24 5:29 AM, MANISH PANDEY wrote: > How about introducing a new rq_affinity ( may be rq_affinity =3D 3) for= =20 > using cpus_equal_capacity() using new flag QUEUE_FLAG_SAME_CAPACITY. >=20 > if (cpu =3D=3D rq->mq_ctx->cpu || > =C2=A0=C2=A0=C2=A0=C2=A0(!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queu= e_flags) && > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 cpus_share_cache(cpu, rq->mq_ctx->cpu) = && > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (test_bit(QUEUE_FLAG_CPU_CAPACITY, &rq-= >q->queue_flags)) > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 && cpus_equal_capacity(cpu, rq->m= q_ctx->cpu))) > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 return false; >=20 > Could you please consider raising similar change, if this seems fine fo= r=20 > all. I'm not sure that a change like the above would be acceptable. What is the performance impact of the above change? Redirecting completion interrupts from a slow core to a fast core causes additional cache misses if the I/O was submitted from a slow core. Are there perhaps use cases for which the above change slows down I/O? Thanks, Bart.