Christoph Hellwig <hch@xxxxxxxxxxxxx> 于2025年8月25日周一 17:21写道： > > On Mon, Aug 25, 2025 at 04:51:27PM +0800, Fengnan Chang wrote: > > No restrictions for now, I think we can enable this by default. > > Maybe better solution is modify in bio.c? Let me do some test first. > > Any kind of numbers you see where this makes a different, including > the workloads would also be very valuable here. 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. >
