On Thu, 18 Feb 2021 14:36:31 -0700 Jens Axboe <[email protected]> wrote:
> Currently we cap the batch count at max(32, 2*nr_online_cpus), which these > days is kind of silly as systems have gotten much bigger than in 2009 when > this heuristic was introduced. > > Bump it to capping it at 256 instead. This has a noticeable improvement > for certain io_uring workloads, as io_uring tracks per-task inflight count > using percpu counters. > It will also make percpu_counter_read() and percpu_counter_read_positive() more inaccurate than at present. Any effects from this will take a while to discover. But yes, worth trying - I'll add it to the post-rc1 pile.
