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Separate stats exist for fuse and flush, that only report requests and sectors stats (others are always 0).
Example of parsing code: parse_proc_iostat() function in [https://src.openvz.org/projects/OVZ/repos/vzstat/browse/src/vzstat.c vzstat.c]
=== I/O schedulers ===
Check available/active I/O schedulers for block device "sda":
# cat /sys/block/sda/queue/scheduler
noop deadline [cfq]
* for "cfq" I/O scheduler: a separate block device line is added in iostat proc file
# cat /proc/bc/100/iostat
flush 100 . 0 0 0 0 0 7389 1893968 0 0
fuse 100 . 0 0 0 0 0 0 0 0 0
sda 100 . 0 0 0 9000 1843380 245216 55845488 245028 188
* for "deadline" I/O scheduler: no additional per-device line is added, iops counters for such devices are added to "flush" line counters (iops limit works)
* for "noop" I/O scheduler: iops are not counted (iops limit does not work)
* for devices with no I/O scheduler (like logical devices, ceph rbd devices, etc): iops are not counted (iops limit does not work)
# cat /sys/block/dm-0/queue/scheduler
none
# cat /sys/block/rbd0/queue/scheduler
none
=== Queues ===
active = sum(b.used_time - a.used_time) * 100 / interval;
waiting = sum(b.wait_time - ba.wait_time) * 100 / interval;
idle = 100 - (active + waiting);
== See also ==
* [[IO accounting]]
* [[I/O priorities for containers]]* [[I/O limits]]