I'm not sure I know exactly how to ask this question but I'll give it a shot. It may be a linux question more so than a snmp question but perhaps someone here has seen this before.
I work in a lab that has to measure software and middleware performance. I have have been using the snmpwalk utility as follows to get User and System space raw counts.
RAWUSR=`snmpwalk -v2c -c commnamegoeshere $HOSTNAME UCD-SNMP-MIB::ssCpuRawUser.0|awk '{print $4}'`
This is run in a 3 second interval and then deltas are taken between the 3 second intervals over a pre determined time, say 30 minutes. From this we can calculate how many user jiffies were used in a 30 minute interval and depict it graphically to form what I call application signatures.
This is where it gets cloudy to me.
In Redhat Enterprise 3 WS and ES, everytime you pull this information it returns a different number which seems to me to suggest that it is getting the data from /proc/stat when you call snmpwalk however in RHEL 4 with the 2.6 kernel the value returned by snmpwalk is only updated every 6 or so seconds while /proc/stat is continually changing.
So now to the question. Where does snmpwalk -v2c -c commnamegoeshere $HOSTNAME UCD-SNMP-MIB::ssCpuRawUser.0 get's this value and is there a way to make it update more frequently?
Any useful suggestion would be appreciated.
Warmongr
I work in a lab that has to measure software and middleware performance. I have have been using the snmpwalk utility as follows to get User and System space raw counts.
RAWUSR=`snmpwalk -v2c -c commnamegoeshere $HOSTNAME UCD-SNMP-MIB::ssCpuRawUser.0|awk '{print $4}'`
This is run in a 3 second interval and then deltas are taken between the 3 second intervals over a pre determined time, say 30 minutes. From this we can calculate how many user jiffies were used in a 30 minute interval and depict it graphically to form what I call application signatures.
This is where it gets cloudy to me.
In Redhat Enterprise 3 WS and ES, everytime you pull this information it returns a different number which seems to me to suggest that it is getting the data from /proc/stat when you call snmpwalk however in RHEL 4 with the 2.6 kernel the value returned by snmpwalk is only updated every 6 or so seconds while /proc/stat is continually changing.
So now to the question. Where does snmpwalk -v2c -c commnamegoeshere $HOSTNAME UCD-SNMP-MIB::ssCpuRawUser.0 get's this value and is there a way to make it update more frequently?
Any useful suggestion would be appreciated.
Warmongr