On 3/8/22 3:17 PM, Olivier Langlois wrote: > The sqpoll thread can be used for performing the napi busy poll in a > similar way that it does io polling for file systems supporting direct > access bypassing the page cache. > > The other way that io_uring can be used for napi busy poll is by > calling io_uring_enter() to get events. > > If the user specify a timeout value, it is distributed between polling > and sleeping by using the systemwide setting > /proc/sys/net/core/busy_poll. > > The changes have been tested with this program: > https://github.com/lano1106/io_uring_udp_ping > > and the result is: > Without sqpoll: > NAPI busy loop disabled: > rtt min/avg/max/mdev = 40.631/42.050/58.667/1.547 us > NAPI busy loop enabled: > rtt min/avg/max/mdev = 30.619/31.753/61.433/1.456 us > > With sqpoll: > NAPI busy loop disabled: > rtt min/avg/max/mdev = 42.087/44.438/59.508/1.533 us > NAPI busy loop enabled: > rtt min/avg/max/mdev = 35.779/37.347/52.201/0.924 us Applied, thanks. -- Jens Axboe
