On Thu, Apr 8, 2021 at 6:59 AM Md Haris Iqbal wrote: > > Hi Jens, > > This version is rebased against the latest for-next. > > Thanks, > Haris > > PATCH V4: https://lore.kernel.org/linux-block/20210203151019.27036-1-guoqing.jiang@cloud.ionos.com/ > * Adds Reviewed-by tag from Johannes. > > PATCH V3: https://lore.kernel.org/linux-block/7f78132a-affc-eb03-735a-4da43e143b6e@cloud.ionos.com/T/#t > * reorgnize the patchset per Johannes's suggestion. > > PATCH V2: https://lore.kernel.org/linux-block/20210201012727.28305-1-guoqing.jiang@cloud.ionos.com/T/#t > *. remove BLK_ADDITIONAL_DISKSTAT option per Christoph's comment. > *. move blk_queue_io_extra_stat into blk_additional_{latency,sector} > per Christoph's comment. > *. simplify blk_additional_latency by pass duration time directly. > > PATCH V1: https://marc.info/?l=linux-block&m=161176000024443&w=2 > * add Jack's reviewed-by. > > RFC V4: https://marc.info/?l=linux-block&m=161027198729158&w=2 > * rebase with latest code. > > RFC V3: https://marc.info/?l=linux-block&m=159730633416534&w=2 > * Move the #ifdef CONFIG_BLK_ADDITIONAL_DISKSTAT into the function body > per Johannes's comment. > * Tweak the output of two tables to make they are more intuitive > > RFC V2: https://marc.info/?l=linux-block&m=159467483514062&w=2 > * don't call ktime_get_ns and drop unnecessary patches. > * add io_extra_stats to avoid potential overhead. > > RFC V1: https://marc.info/?l=linux-block&m=159419516730386&w=2 > > Guoqing Jiang (3): > block: add io_extra_stats node > block: add a statistic table for io latency > block: add a statistic table for io sector We've also found it useful to have the kernel export latency statistics. In particular we've been using a 2d-histogram exporting latency per iosize (there was a proposal a loong time ago that seemed to fizzle out https://lwn.net/Articles/383515/) Do you think having a format like that would be useful? # cat /sys/block/sda/read_request_histo rows = bytes columns = ms 10 20 50 100 200 500 1000 2000 5000 10000 20000 2048 33 0 0 0 0 0 0 0 0 0 0 4096 51798 1114 1271 11 0 0 0 0 0 0 0 8192 8803 81 109 1 0 0 0 0 0 0 0 16384 10321 116 150 5 0 0 0 0 0 0 0 32768 8341 166 215 6 0 0 0 0 0 0 0 65536 7550 248 389 2 0 0 0 0 0 0 0 131072 40440 923 1317 10 0 0 0 0 0 0 0 262144 357 1 0 0 0 0 0 0 0 0 0 524288 13 1 0 0 0 0 0 0 0 0 0 1048576 7 2 0 0 0 0 0 0 0 0 0 Khazhy