On 05/21/2013 08:51 PM, Liu Yuan wrote: > On 05/21/2013 08:44 PM, MORITA Kazutaka wrote: >> Yes. Can you prepare a patch to drop O_DIRECT from the open flag when >> offset and length are not sector aligned? I think the patch should be >> in the same series with this one. > > Not all the system support diretio. I am wondering if we can do the > trick in the collie? Collie just do a block-aligned read/write, but > return the right thing for read? Oops, what I meant is that switching from directio to buffered IO is too costy, directio is very useful for running many VMs that don't consume memory much and get a consistent performance. Thanks, Yuan |