Messages in this thread | | | Subject | Re: [PATCH RFC] scsi: core: remove unsed 'restarts' from scsi_device | From | Yu Kuai <> | Date | Sat, 26 Nov 2022 16:54:46 +0800 |
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Hi,
在 2022/11/18 19:30, Yu Kuai 写道: > From: Yu Kuai <yukuai3@huawei.com> > > During code review, I found that 'restarts' is not useful anymore after > the following commits: > > 1) commit ab3cee3762e5 ("blk-mq: In blk_mq_dispatch_rq_list() "no budget" > is a reason to kick") > 2) commit d3b38596875d ("blk-mq: run queue no matter whether the request > is the last request") > 3) commit 673235f91531 ("scsi: core: Fix race between handling STS_RESOURCE > and completion") > > Now that if get budget ever failed, block layer will make sure to > trigger new run queue for the hctx. Hence there is no need to run queue > from scsi layer in this case. >
Does anyone has suggestions about this patch?
More info why I tried to remove this:
while testing megaraid with 4 nvme with none elevator, the default queue_depth is 128, while I test it with fio 128 jobs and 1 iodepth, bw is about 4Gib/s, however, if I test with 128 jobs and 2 iodepth, bw is decreased to about 0.8Gib/s, and with this patch applied, bw can stay 4Gib/s in the later case.
Thanks, Kuai
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