Simplified estimation for io_ticks introduced in patch https://lore.kernel.org/linux-block/20181206164122.2166-5-snitzer@xxxxxxxxxx/ could be very inaccurate for request longer than jiffy (i.e. any HDD) There is at least one another report about this: https://lore.kernel.org/linux-block/20200324031942.GA3060@ming.t460p/ See detail in comment for first patch. v1: https://lore.kernel.org/lkml/155413438394.3201.15211440151043943989.stgit@buzz/ v2: https://lore.kernel.org/lkml/158314549775.1788.6529015932237292177.stgit@buzz/ v3: * update documentation * rebase to current linux-next * fix compilation for CONFIG_SMP=n --- Konstantin Khlebnikov (3): block/diskstats: more accurate approximation of io_ticks for slow disks block/diskstats: accumulate all per-cpu counters in one pass block/diskstats: replace time_in_queue with sum of request times Documentation/admin-guide/iostats.rst | 5 ++- block/bio.c | 9 ++--- block/blk-core.c | 5 +-- block/genhd.c | 64 +++++++++++++++++++++++++-------- block/partition-generic.c | 39 ++++++++++++-------- include/linux/genhd.h | 14 +++++-- 6 files changed, 90 insertions(+), 46 deletions(-) -- Signature
