On 3/22/21 10:49 PM, Jens Axboe wrote: > On 3/21/21 11:54 PM, Xiaoguang Wang wrote: >> hi Pavel, >> >>> Hey, >>> >>> You may have already noticed, but there will be a change how SQPOLL >>> is shared in 5.12. In particular, SQPOLL may be shared only by processes >>> belonging to the same thread group. If this condition is not fulfilled, >>> then it silently creates a new SQPOLL task. >> >> Thanks for your kindly reminder, currently we only share sqpoll thread >> in threads belonging to one same process. > > That's good to know, imho it is also the only thing that _really_ makes > sense to do. > > Since we're on the topic, are you actively using the percpu thread setup > that you sent out patches for earlier? That could still work within > the new scheme of having io threads, but I'd be curious to know first > if you guys are actually using it. > Yes, we've already used percpu sqthread feature in our production environment, in which 16 application threads share the same sqthread, and it gains ~20% rt improvement compared with libaio. Thanks, Joseph
