svcinfo lssystem
About 15 lines down you should see the following:
statistics_status on
statistics_frequency 15
If
statistics_status is off, then you need to switch it on.
The second line is the frequency at which statistics will be collected.
This is specified in minutes and can be between 1 and 60. To turn this
on, or change the frequency, use the
startstats command:
svctask startstats -interval interval
Bear in mind if you use and interval of 1 minute, you will get a
lot of stats, but doing so will make it easier to catch small spikes in performance.
Once statistics collection is running, you need to copy the resulting
files from the cluster. Note that each node on the cluster will collect
stats for that node only, so if you simply copy stats from the cluster,
you will only copy them from the configuration node. Note also that each
node will contain a
maximum of 16 sets of stats files. Further stats collections will overwrite old files.
So bearing this in mind, you need to first copy the files from the
non-configuration nodes to the configuration node before copying them
from the cluster, and you also need to do this frequently to make sure
you collect all the stats. If the
statistics_frequency is
X minutes, then this period will be
16 * X at
the most. There is no harm in collecting statistics more frequently, as
scp will simply overwrite duplicate files. I generally collect them at
the same period as
statistics_frequency in order to ensure I have a copy of the latest stats.
The collection needs to be performed on a host, such as the SSPC. You
can use a Unix host with a cron job, or even a while loop using the
sleep command to set the interval, or use a scheduled task on a Windows
host. The script itself is two lines, and can be run as a cmd or shell
script.
ssh admin@ "svcinfo lsnode -nohdr -filtervalue config_node=no|while read -a node; do svctask cpdumps -prefix /dumps/iostats ${node[0]}; done"
scp admin@:/dumps/iostats/*
Choose suitable values for the destination for the files on the local host.
Note that if you're running this from a local Unix shell, you must
escape the $, i.e. use \${node[0]}. If you don't the shell will try to
substitute a local variable, which doesn't exist.
Note also that the filter value "config_node" is only implemented in
later code. You'll need to remove this for earlier code levels. You'll
get an error when the cpdumps command is run but the files will all copy
OK nevertheless.
Once you have set this up as a cron job or scheduled task, you should find
filling up with statistics ready for analysis, which is a more complicated subject.
Here's an example of a short cmd script which will use the $clust
environment variable on the cluster to fetch the name of the cluster.
The files will be fetched and added to an appropriately named zip file. I
use Cygwin rather than Putty for this, but you could easily modify to
use plink and pscp
set SVC=%1
set ZIP="C:\Program Files\7-zip\7z.exe"
for /f %%i in ('ssh admin@%SVC% echo $clust') do set NAME=%%i
ssh admin@%SVC% "svcinfo lsnode -nohdr |while read -a node; do svctask cpdumps -prefix /dumps/iostats $node; done"
scp admin@%SVC%:/dumps/iostats/* .
%ZIP% u -tzip -mx9 stats_%NAME%.zip *_stats_*
if [%errorlevel%]==[0] del *_stats_*
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