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