Understanding Purepath Breakdown

Hi Anurag

Here is an explaination that I copied from one of our internal forums - this should give you enough explanation to understand the individual values you see in the PP Dashlet:

first of all you have to differentiate the breakdown of PurePaths and the breakdown of methods:

• PurePath breakdown: this breakdown relates to the sum of all methods/subpaths, NOT the response time and NOT the duration
• method breakdown: this breakdown relates to the total time of the method (including called methods)

what we measure exactly (meaning: by instrumentation and callbacks) is:

• total exec time of methods (= 100% of the method breakdown)
• total CPU time of methods
• suspension time inside methods (more exactly: over all currently executed methods)

by using the information from the called methods, we get for each method in the PurePath:

• exec time (only this method)
• CPU time (only this method)
• total suspension time (this method and all called methods)

additionally, by using auto sensors and thread states we also get (additional to timings for non-instrumented methods)

• wait time of methods
• sync time of methods

and, as already said, the remainder which is left is then declared as "IO".

As to your specific question on IO and socketread(). This simply means that your PurePath is reading data from the network - and therefore it is considered IO. If socketread is a call you see "underneath" your JDBC calls you know it is related to retrieving data from the database server. If you see lots of socketread you may want to check whether the application is requesting a lot of data that takes a long time to transfer. Or - maybe your network bandwidth is limited and thats why socketread takes that long. It could however also be that your database server is overloaded and therefore socketread takes that long

Hope this helps

hi Anurag,

about your question and in addition to the (very good ) explanation above:

sync time: time that a thread waits for a resource that another thread currently occupies (usually by "synchronized" or some other java.concurrency locks).

wait time: time that a thread waits on a specific object to be notified by another thread (usually by Object.wait() and Object.notify()/notifyAll()).

hope this helps, Christian

Especially we are seeing a lot of IO time due to socketread ()

Can you please advise what does that indicate

Thanks Andreas. That really helps !! I under stand that suspensions time is the time when the JAVA runtime is suspended for GC and this be handeled by a proper memory management .  Also, CPU time is the time when the CPU is busy in processing the request. Could you please explain what is the

a) wait time of methods

b) sync time of methods

and what is the general cause of encountering them.

Thanks a lot !!