On 30/07/2020 21:08, Jens Axboe wrote: > On 7/30/20 9:43 AM, Pavel Begunkov wrote: >> [1/1] takes apart the union, too much trouble and there is no reason >> left for keeping it. Probably for 5.10 we can reshuffle the layout as >> discussed. > > Let's hope so, because I do think this is the safest option, but it does > incur a 5% drop for me. Hmm, any ideas why? If your test doesn't use neither apoll/poll/io-wq, then it looks like either something related to slab (e.g. partial zeroing), or magic with @task_work moved from 4th to 3rd cacheline. > > We could probably make this work for 5.9 as well, depending on if there > is an -rc8 or not. Seems like there will be, hence we're a week and a > half out from the merge window. > -- Pavel Begunkov
