blkparse 如何显示 IO 调度程序消息
blkparse how to show IO Scheduler message
blktrace 版本 v2.0.0
注意：在blkparse输出中，第六列的m表示该行是调度器信息。
在 Ubuntu 16.04 ext4 我可以看到 IO 调度程序消息，blktrace -d /dev/sda -o - | blkparse -i -
8,0 3 1 0.000000000 24714 A WS 76519424 + 2048 <- (8,1) 76517376
8,0 3 2 0.000000861 24714 Q WS 76519424 + 2048 [TaskSchedulerFo]
8,0 3 3 0.000005084 24714 X WS 76519424 / 76520768 [TaskSchedulerFo]
8,0 3 4 0.000008962 24714 G WS 76519424 + 1344 [TaskSchedulerFo]
8,0 3 5 0.000009379 24714 P N [TaskSchedulerFo]
8,0 3 6 0.000012021 24714 G WS 76520768 + 704 [TaskSchedulerFo]
8,0 3 7 0.000012622 24714 I WS 76519424 + 1344 [TaskSchedulerFo]
8,0 3 0 0.000015209 0 m N cfq24714SN /user.slice insert_request
8,0 3 0 0.000016074 0 m N cfq24714SN /user.slice add_to_rr
8,0 3 0 0.000017548 0 m N cfq24714SN /user.slice preempt
8,0 3 0 0.000018184 0 m N cfq25055SN /user.slice slice expired t=1
8,0 3 0 0.000018982 0 m N cfq25055SN /user.slice resid=-2643710186
8,0 3 0 0.000020125 0 m N /user.slice served: vt=247310740068 min_vt=247310580285
8,0 3 0 0.000021297 0 m N cfq25055SN /user.slice sl_used=33325195 disp=13 charge=13 iops=1 sect=1088
8,0 3 0 0.000021822 0 m N cfq25055SN /user.slice del_from_rr
8,0 3 0 0.000023767 0 m N cfq workload slice:100000000
8,0 3 0 0.000024496 0 m N cfq24714SN /user.slice set_active wl_class:0 wl_type:1
8,0 3 0 0.000025395 0 m N cfq24714SN /user.slice dispatch_insert
8,0 3 0 0.000026232 0 m N cfq24714SN /user.slice dispatched a request
8,0 3 0 0.000026818 0 m N cfq24714SN /user.slice activate rq, drv=1
8,0 3 8 0.000027030 24714 D WS 76519424 + 1344 [TaskSchedulerFo]
8,0 3 9 0.000037848 24714 U N [TaskSchedulerFo] 1
8,0 3 10 0.000038118 24714 P N [TaskSchedulerFo]
8,0 3 11 0.000048153 24714 A WS 76521472 + 264 <- (8,1) 76519424
8,0 3 12 0.000048340 24714 Q WS 76521472 + 264 [TaskSchedulerFo]
8,0 3 13 0.000049444 24714 M WS 76521472 + 264 [TaskSchedulerFo]
8,0 3 14 0.000050486 24714 I WS 76520768 + 968 [TaskSchedulerFo]
8,0 3 0 0.000051332 0 m N cfq24714SN /user.slice insert_request
8,0 3 15 0.000051755 24714 U N [TaskSchedulerFo] 1
8,0 3 0 0.000052418 0 m N cfq24714SN /user.slice dispatch_insert
8,0 3 0 0.000053068 0 m N cfq24714SN /user.slice dispatched a request
8,0 3 0 0.000053604 0 m N cfq24714SN /user.slice activate rq, drv=2
8,0 3 16 0.000053721 24714 D WS 76520768 + 968 [TaskSchedulerFo]
8,0 2 1 0.001844211 0 C WS 76519424 + 1344 [0]
8,0 2 0 0.001849143 0 m N cfq24714SN /user.slice complete rqnoi
在 CentOS 7.4 xfs，我看不到 IO Scheduler 消息，blktrace -d /dev/sdb -o - | blkparse -i -
8,16 25 1 0.000000000 11966 Q R 73400472 + 128 [fio]
8,16 25 2 0.000006237 11966 G R 73400472 + 128 [fio]
8,16 25 3 0.000007806 11966 P N [fio]
8,16 25 4 0.000010836 11966 I R 73400472 + 128 [fio]
8,16 25 5 0.000011878 11966 U N [fio] 1
8,16 25 6 0.000013900 11966 D R 73400472 + 128 [fio]
8,16 10 1 0.008284979 0 C R 73400472 + 128 [0]
8,16 10 2 0.008343574 11966 Q R 73400600 + 128 [fio]
8,16 10 3 0.008345976 11966 G R 73400600 + 128 [fio]
8,16 10 4 0.008346908 11966 P N [fio]
8,16 10 5 0.008348926 11966 I R 73400600 + 128 [fio]
8,16 10 6 0.008349651 11966 U N [fio] 1
8,16 10 7 0.008350694 11966 D R 73400600 + 128 [fio]
8,16 8 1 0.008771249 0 C R 73400600 + 128 [0]
虽然设置之间存在程序版本差异（在 CentOS 7 blktrace is version 1.0.5 and the kernel is based off 3.10 whereas in Ubuntu 16.04 blktrace is version 1.1.0 and the kernel may be between 4.4 - 4.10) the real point may be down to what was asked 中（但不幸的是没有得到答复）在其中一条评论中：
what [I/O] scheduler was in use
如果我们查看您的 m 行之一：
8,0 3 0 0.000015209 0 m N cfq24714SN /user.slice insert_request
我们可以看到它是 textual message (hence the m) and that it likely came from the CFQ I/O scheduler (hence the cfq prefix on the message itself). If the I/O scheduler being used for the /dev/sdb device on the CentOS 7 setup was not CFQ (e.g. because the noop I/O scheduler 被使用）那么我们不能指望会出现类似的消息。
所以回到问题的标题：
blkparse how to show IO Scheduler message
如果 I/O 调度程序想要它可以发送自由格式 blktrace 文本（例如参见 [=21=].
blktrace 版本 v2.0.0
注意：在blkparse输出中，第六列的m表示该行是调度器信息。
在 Ubuntu 16.04
ext4我可以看到 IO 调度程序消息，blktrace -d /dev/sda -o - | blkparse -i -8,0 3 1 0.000000000 24714 A WS 76519424 + 2048 <- (8,1) 76517376 8,0 3 2 0.000000861 24714 Q WS 76519424 + 2048 [TaskSchedulerFo] 8,0 3 3 0.000005084 24714 X WS 76519424 / 76520768 [TaskSchedulerFo] 8,0 3 4 0.000008962 24714 G WS 76519424 + 1344 [TaskSchedulerFo] 8,0 3 5 0.000009379 24714 P N [TaskSchedulerFo] 8,0 3 6 0.000012021 24714 G WS 76520768 + 704 [TaskSchedulerFo] 8,0 3 7 0.000012622 24714 I WS 76519424 + 1344 [TaskSchedulerFo] 8,0 3 0 0.000015209 0 m N cfq24714SN /user.slice insert_request 8,0 3 0 0.000016074 0 m N cfq24714SN /user.slice add_to_rr 8,0 3 0 0.000017548 0 m N cfq24714SN /user.slice preempt 8,0 3 0 0.000018184 0 m N cfq25055SN /user.slice slice expired t=1 8,0 3 0 0.000018982 0 m N cfq25055SN /user.slice resid=-2643710186 8,0 3 0 0.000020125 0 m N /user.slice served: vt=247310740068 min_vt=247310580285 8,0 3 0 0.000021297 0 m N cfq25055SN /user.slice sl_used=33325195 disp=13 charge=13 iops=1 sect=1088 8,0 3 0 0.000021822 0 m N cfq25055SN /user.slice del_from_rr 8,0 3 0 0.000023767 0 m N cfq workload slice:100000000 8,0 3 0 0.000024496 0 m N cfq24714SN /user.slice set_active wl_class:0 wl_type:1 8,0 3 0 0.000025395 0 m N cfq24714SN /user.slice dispatch_insert 8,0 3 0 0.000026232 0 m N cfq24714SN /user.slice dispatched a request 8,0 3 0 0.000026818 0 m N cfq24714SN /user.slice activate rq, drv=1 8,0 3 8 0.000027030 24714 D WS 76519424 + 1344 [TaskSchedulerFo] 8,0 3 9 0.000037848 24714 U N [TaskSchedulerFo] 1 8,0 3 10 0.000038118 24714 P N [TaskSchedulerFo] 8,0 3 11 0.000048153 24714 A WS 76521472 + 264 <- (8,1) 76519424 8,0 3 12 0.000048340 24714 Q WS 76521472 + 264 [TaskSchedulerFo] 8,0 3 13 0.000049444 24714 M WS 76521472 + 264 [TaskSchedulerFo] 8,0 3 14 0.000050486 24714 I WS 76520768 + 968 [TaskSchedulerFo] 8,0 3 0 0.000051332 0 m N cfq24714SN /user.slice insert_request 8,0 3 15 0.000051755 24714 U N [TaskSchedulerFo] 1 8,0 3 0 0.000052418 0 m N cfq24714SN /user.slice dispatch_insert 8,0 3 0 0.000053068 0 m N cfq24714SN /user.slice dispatched a request 8,0 3 0 0.000053604 0 m N cfq24714SN /user.slice activate rq, drv=2 8,0 3 16 0.000053721 24714 D WS 76520768 + 968 [TaskSchedulerFo] 8,0 2 1 0.001844211 0 C WS 76519424 + 1344 [0] 8,0 2 0 0.001849143 0 m N cfq24714SN /user.slice complete rqnoi在 CentOS 7.4
xfs，我看不到 IO Scheduler 消息，blktrace -d /dev/sdb -o - | blkparse -i -8,16 25 1 0.000000000 11966 Q R 73400472 + 128 [fio] 8,16 25 2 0.000006237 11966 G R 73400472 + 128 [fio] 8,16 25 3 0.000007806 11966 P N [fio] 8,16 25 4 0.000010836 11966 I R 73400472 + 128 [fio] 8,16 25 5 0.000011878 11966 U N [fio] 1 8,16 25 6 0.000013900 11966 D R 73400472 + 128 [fio] 8,16 10 1 0.008284979 0 C R 73400472 + 128 [0] 8,16 10 2 0.008343574 11966 Q R 73400600 + 128 [fio] 8,16 10 3 0.008345976 11966 G R 73400600 + 128 [fio] 8,16 10 4 0.008346908 11966 P N [fio] 8,16 10 5 0.008348926 11966 I R 73400600 + 128 [fio] 8,16 10 6 0.008349651 11966 U N [fio] 1 8,16 10 7 0.008350694 11966 D R 73400600 + 128 [fio] 8,16 8 1 0.008771249 0 C R 73400600 + 128 [0]
虽然设置之间存在程序版本差异（在 CentOS 7 blktrace is version 1.0.5 and the kernel is based off 3.10 whereas in Ubuntu 16.04 blktrace is version 1.1.0 and the kernel may be between 4.4 - 4.10) the real point may be down to what was asked 中（但不幸的是没有得到答复）在其中一条评论中：
what [I/O] scheduler was in use
如果我们查看您的 m 行之一：
8,0 3 0 0.000015209 0 m N cfq24714SN /user.slice insert_request
我们可以看到它是 textual message (hence the m) and that it likely came from the CFQ I/O scheduler (hence the cfq prefix on the message itself). If the I/O scheduler being used for the /dev/sdb device on the CentOS 7 setup was not CFQ (e.g. because the noop I/O scheduler 被使用）那么我们不能指望会出现类似的消息。
所以回到问题的标题：
blkparse how to show IO Scheduler message
如果 I/O 调度程序想要它可以发送自由格式 blktrace 文本（例如参见 [=21=].