wspy – memory analysis for processes; need to sanity check the metrics…
As a followup to this post, I’ve implemented per-process capture of backend counters. I can now create a memory report from a process tree.
Continue reading →As a followup to this post, I’ve implemented per-process capture of backend counters. I can now create a memory report from a process tree.
Continue reading →I have added a new mode: –perfcounter-model application this supplements the previous two modes: –perfcounter-model process –perfcounter-model core This mode works similar to the process model, except only the root process is instrumented and then the “inherit” flag is passed. … Continue reading →
The ptrace(2) man page shows how one can subscribe for events such as PTRACE_EVENT_FORK or PTRACE_EVENT_VFORK type events that happens when a process calls fork()/vfork(). At such an event one can then call ptrace(PTRACE_GETEVENTMSG,…) to retrieve the pid of the … Continue reading →
As a followup to a previous post, I’ve added support to wspy for topdown analysis for backend stalls.
Continue reading →One of the tough bugs I’ve noticed sometimes pop up is an “orphaned” process tree in my tree. When I’ve collected trees of processes, very occasionally I’ll have a tree node drop on the floor and show up as an … Continue reading →
I have updated wspy to dump a “processtable.csv” file at the same time it dumps a “processtable.txt” file. This gives me several advantages: I’ve separated the format of output from collecting instrumentation. Hence, I can run things once to collect … Continue reading →
As described in top down performance counter analysis part 1, top down analysis is an approach that uses key performance counters to characterize an application and then successively drills down with further refinement. On Intel x86 processors, this first level … Continue reading →
As described in top down performance counter analysis part 1, top down analysis is an approach that uses key performance counters to characterize an application and then successively drills down with further refinement. On Intel x86 processors, this first level … Continue reading →
wspy is both a code base and a tool for performance analysis. As a code base, I modify wspy to run particular experiments and measurements. This lets me experiment trying particular techniques and interfaces to create a quick and dirty … Continue reading →
wspy is now enhanced to provide two new metrics, for a particular process tree: on_cpu – what percentage of the total time are all the cores scheduled to run in either user or system time? on_core – what percentage of … Continue reading →