Did you know tw_cli has performance monitoring??

Yep title says it all, you can actually monitor individual disk performance with tw_cli.

First we need to enable performance monitoring:

tw_cli /c0 set dpmstat=on

Now we will show the information its providing.

tw_cli /c0 show dpmstat  type=ra
Drive Performance Monitor Configuration for /c0 ...
Performance Monitor: ON
Version: 1
Max commands for averaging: 100
Max latency commands to save: 10
Requested data: Running Average Drive Statistics

 Queue           Xfer         Resp
Port   Status           Unit   Depth   IOPs    Rate(MB/s)   Time(ms)
------------------------------------------------------------------------
p0     OK               u0     22      23      0.479        11
p1     OK               u0     24      93      1.344        12
p2     OK               u0     25      82      0.720        14
p3     OK               u0     24      83      1.108        16

BE SURE TO TURN OFF PERFORMANCE MONITORING WHEN YOU ARE DONE!

tw_cli /c0 set dpmstat=off

Different performance results:

This command only applies to 9000 series SX/SE/SA controllers, except for
type=ext, which applies only to SE/SA models.

This command allows you to request drive statistics of the specified type for
the specified port. These statistics can be helpful when troubleshooting
performance problems.

type= specifies which statistics should be displayed. The options are: inst for
Instantaneous, ra for Running Average, lct for Long Command Times,
histdata for Histogram Data, and ext for Extended Drive Statistics.

inst (Instantaneous). This measurement provides a short duration average.
ra (Running Average). Running average is a measure of long-term averages
that smooth out the data, and results in older results fading from the average
over time.

ext (Extended Drive Statistics). The extended drive statistics refers to
statistics of a drive’s read commands, write commands, write commands with
FUA (Force Unit Access), flush commands, and a drive sectors’s read, write,
and write commands with FUA.

lct (Long Command Times). This a collection of the commands with the
longest read/write response time.

histdata (Histogram Data). The histogram categorizes the read/write
execution times and group them together based on time frames.

Leave a Reply

Your email address will not be published. Required fields are marked *