linux/Documentation/block
Konstantin Khlebnikov b686631865 block: add iostat counters for flush requests
Requests that triggers flushing volatile writeback cache to disk (barriers)
have significant effect to overall performance.

Block layer has sophisticated engine for combining several flush requests
into one. But there is no statistics for actual flushes executed by disk.
Requests which trigger flushes usually are barriers - zero-size writes.

This patch adds two iostat counters into /sys/class/block/$dev/stat and
/proc/diskstats - count of completed flush requests and their total time.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-21 09:06:47 -07:00
..
bfq-iosched.rst
biodoc.rst
biovecs.rst
capability.rst
cmdline-partition.rst
data-integrity.rst
deadline-iosched.rst
index.rst
ioprio.rst
kyber-iosched.rst
null_blk.rst
pr.rst
queue-sysfs.rst
request.rst
stat.rst block: add iostat counters for flush requests 2019-11-21 09:06:47 -07:00
switching-sched.rst
writeback_cache_control.rst