kernel_optimize_test/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 docs: cgroup-v1: add it to the admin-guide book 2019-07-15 11:03:02 -03:00
biodoc.rst docs conversion for v5.3-rc1 2019-07-16 12:21:41 -07:00
biovecs.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
capability.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
cmdline-partition.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
data-integrity.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
deadline-iosched.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
index.rst docs: add some documentation dirs to the driver-api book 2019-07-15 11:03:02 -03:00
ioprio.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
kyber-iosched.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
null_blk.rst docs: block: null_blk: enhance document style 2019-09-11 16:04:22 -06:00
pr.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
queue-sysfs.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
request.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
stat.rst block: add iostat counters for flush requests 2019-11-21 09:06:47 -07:00
switching-sched.rst Documenation: switching-sched: Remove notes about elevator argument 2019-09-03 08:04:02 -06:00
writeback_cache_control.rst docs: block: convert to ReST 2019-07-15 09:20:27 -03:00