Sensor configuration capture cpu time setting
Hi,
can I get some advice on the setting of Sensor property 'Capture Cpu Time'. This can be set to Automatic, enabled or disabled. Explanation of Automatic is somewhat cryptic (enabled until overhead is determined to be too high?). Due to this, some are in favour of setting it completely disabled, specially for heavy loaded jvm's. The perception is that monitoring method cpu time will slowdown the request, is this correct?
Wim.
Currently we use dT 5.5, 6.0 sits in the pipeline.
hi Wim,
usually you're fine with 'automatic'.
the background is that in the past we experienced some performance impact by capturing CPU times on specific JVMs (I think it was IBM) and platforms (some specific linux kernel versions). this is why we introduced this automatic mode where we check for such JVMs/platforms and disable CPU capturing automatically.
best,
Christian
Hi Chris,
we run IBM Websphere V7 on RHEL2.6, would that be a problem?
Wim.
hi Wim,
I can't tell you by heart. but again: if we would know it could be an issue, then 'automatic' would turn CPU capturing off, anyway.
the only real way of figuring out if CPU capturing has an impact in your environment is to try it out yourself by running reproducible transactions with and without CPU capturing and look at the differences.
best,
Chris
OK
One last question: if I set CPU Capturing off in the sensor configuration, do I need to restart the jvm to deactivate or is the setting deactivated imediately?
Wim.
