On 9/23/22 9:21 AM, Christoph Hellwig wrote: > On Fri, Sep 23, 2022 at 09:19:15AM -0600, Jens Axboe wrote: >> On 9/23/22 9:16 AM, Christoph Hellwig wrote: >>> On Thu, Sep 22, 2022 at 12:28:00PM -0600, Jens Axboe wrote: >>>> This is good for a 10% improvement for passthrough performance. For >>>> a non-drive limited test case, passthrough IO is now more efficient >>>> than the regular bdev O_DIRECT path. >>> >>> How so? If it ends up faster we are doing something wrong in the >>> normal path as there should be no fundamental difference in the work >>> that is being done. >> >> There's no fundamental difference, but the bdev path is more involved >> than the simple passthrough path. > > Well, I guess that means there is some more fat we need to trim > then.. Yes and no, there's always more fat to trim. But some of it is inevitable, so... -- Jens Axboe
