Christoph Hellwig [off-list ref] 于2025年8月25日周一 18:48写道：

On Mon, Aug 25, 2025 at 05:41:57PM +0800, Fengnan Chang wrote:

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I'm test random direct read performance on  io_uring+ext4, and try
compare to io_uring+ raw blkdev,  io_uring+ext4 is quite poor, I'm try to
improve this, I found ext4 is quite different with blkdev when run
bio_alloc_bioset. It's beacuse blkdev ext4  use percpu bio cache, but ext4
path not. So I make this modify.
My test command is:
/fio/t/io_uring -p0 -d128 -b4096 -s1 -c1 -F1 -B1 -R1 -X1 -n1 -P1 -t0
/data01/testfile
Without this patch:
BW is 1950MB
with this patch
BW is 2001MB.

Interesting.  This is why the not yet merged ext4 iomap patches I guess?
Do you see similar numbers with XFS?

Yes, similar numbers with XFS.

quoted