Hi Jan and Jens On 6/25/20 12:51 PM, Jan Kara wrote: > On Wed 17-06-20 15:58:23, Jan Kara wrote: >> Currently blk-mq does not report any event when two requests get merged >> in the elevator. This then results in difficult to understand sequence >> of events like: >> >> ... >> 8,0 34 1579 0.608765271 2718 I WS 215023504 + 40 [dbench] >> 8,0 34 1584 0.609184613 2719 A WS 215023544 + 56 <- (8,4) 2160568 >> 8,0 34 1585 0.609184850 2719 Q WS 215023544 + 56 [dbench] >> 8,0 34 1586 0.609188524 2719 G WS 215023544 + 56 [dbench] >> 8,0 3 602 0.609684162 773 D WS 215023504 + 96 [kworker/3:1H] >> 8,0 34 1591 0.609843593 0 C WS 215023504 + 96 [0] >> >> and you can only guess (after quite some headscratching since the above >> excerpt is intermixed with a lot of other IO) that request 215023544+56 >> got merged to request 215023504+40. Provide proper event for request >> merging like we used to do in the legacy block layer. >> >> Signed-off-by: Jan Kara<jack@xxxxxxx> > Jens, it seems people are fine with this patch in the end. Can you please > merge it? Thanks! > I'm sending blktrace cleanup based on the discussion [1], if you guys want I can also add this patch and keep Jan Author and have cleanup done with this patch included separtely. Please let me know that is not accepted I'll send my series separately. [1] https://marc.info/?l=linux-block&m=159296928424805&w=2 >
