On 1/31/20 5:31 PM, Pavel Begunkov wrote: > On 01/02/2020 01:32, Pavel Begunkov wrote: >> On 01/02/2020 01:22, Jens Axboe wrote: >>> On 1/31/20 3:15 PM, Pavel Begunkov wrote: >>>> Apart from unrelated first patch, this persues two goals: >>>> >>>> 1. start preparing io_uring to move resources handling into >>>> opcode specific functions >>>> >>>> 2. make the first step towards long-standing optimisation ideas >>>> >>>> Basically, it makes struct io_submit_state embedded into ctx, so >>>> easily accessible and persistent, and then plays a bit around that. >>> >>> Do you have any perf/latency numbers for this? Just curious if we >>> see any improvements on that front, cross submit persistence of >>> alloc caches should be a nice sync win, for example, or even >>> for peak iops by not having to replenish the pool for each batch. >>> >>> I can try and run some here too. >>> >> >> I tested the first version, but my drive is too slow, so it was only nops and >> hence no offloading. Honestly, there waren't statistically significant results. >> I'll rerun anyway. >> >> I have a plan to reuse it for a tricky optimisation, but thinking twice, I can >> just stash it until everything is done. That's not the first thing in TODO and >> will take a while. >> > > I've got numbers, but there is nothing really interesting. Throughput is > insignificantly better with the patches, but I'd need much more experiments > across reboots to confirm that. > > Let's postpone the patchset for later Sounds fine to me, no need to do it unless it's a nice cleanup, and/or provides some nice improvements. It would be great to see the splice stuff revamped, though :-) -- Jens Axboe
