> When running perf stat -I for monitoring e.g. PCIe uncore counters and > at the same time profiling some I/O workload by perf record e.g. for > cpu-cycles and context switches, it is then possible to build and > observe good-enough consolidated CPU/OS/IO(Uncore) performance picture > for that workload.
At some point I still hope we can make uncore measurements in perf record work. Kan tried at some point to allow multiple PMUs in a group, but was not successfull. But perhaps we can sample them from a software event instead. > > The warning on possible runtime overhead is still preserved, however > it is only visible when specifying -v option. I would print it unconditionally. Very few people use -v. BTW better of course would be to occasionally measure the perf stat cpu time and only print the warning if it's above some percentage of a CPU. But that would be much more work. Rest looks ok. -Andi
