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The issue seems to be just eager time querying, and using essentially the wrong interface. Patch 1 gets rid of getrusage() for this, and patch 2 attempts to be a bit smarter in how often the time needs to get queried. Profile results in patch 2 as well. io_uring/fdinfo.c | 9 ++++--- io_uring/sqpoll.c | 67 +++++++++++++++++++++++++++++++++-------------- io_uring/sqpoll.h | 1 + 3 files changed, 53 insertions(+), 24 deletions(-) [1] https://lore.kernel.org/io-uring/20251020113031.2135-1-changfengnan@bytedance.com/ -- Jens Axboe