I am trying to understand a simple example and wonder why I don't see more false sharing than reported by perf c2c. In my example (a matrix multiplication), two instances could cause false sharing ...

I tried giving the below command from container and found the below issue, may be because of "-moby" kernel version. Can't we get a docker image without word "-moby" coming in linux kernel version....

I am trying to use the perf tool inside a Docker container to record a given command. kernel.perf_event_paranoid is set to 1, but the container behaves just as if it were 2, when I don't put the -...

I am trying to use the perf tool of Linux on my WSL2 using Windows10 machine. I have done every step of the accepted answer here:Is there any method to run perf under WSL? When I ran "make&quo...

I'm trying to profile with perf on Ubuntu 20.04, but the problem is that many functions do not appear in it (likely because they are inlined), or only their addresses appear (without names etc.). I...

I'm collecting some profiling information on intel using perf record about taken branches and I'm using -b to make use of LBR. Is there any similar support on ARM and PowerPC? And yes I've seen thi...

When I wanted to run perf under WSL, I met the follow question: WARNING: perf not found for kernel 4.4.0-18362 You may need to install the following packages for this specific kernel: linu...

I know perf can profile a single process or single thread use perf stat -p tid/pid or perf top -p tid/pid. But I want to profile per-thread in a process, getting separate results for each and every...

When I want to generate performance reports using perf-stat and perf-report from the Linux tool suite perf, I run: $ perf record -o my.perf.data myCmd $ perf report -i my.perf.data And: $ perf ...

Question In Perf’s annotate view, the runtime consumed by each instruction is given on the left side as a percentage. Is there some option to have some absolute quantity (probably samples) displaye...

For example, def test(): print "test" I used perf record -g -p $pid, but the result was just all about PyEval_EvalFrameEx. How can I get the real name "test" or if can not by using perf?

I have compiled perf for my kernel (3.11.10). During the compilation, some libraries were missing, so I have installed those. But now when I run perf, I get following message: Couldn't record kerne...

I have a program that runs on a multi-thread framework with Linux kernel 4.18 and Intel CPU. I ran perf record -p pid -g -e cycles:u --call-graph lbr -F 99 -- sleep 20 to collect stack trace and ge...

First things first: Alpine Version 3.9.0 perf[from:http://dl-cdn.alpinelinux.org/alpine/edge/testing] 4.18.13 Docker 18.09.3 build 774a1f4 My Dockerfile FROM alpine:latest # Set the working d...

I'm using perf for profiling on Ubuntu 20.04 (though I can use any other free tool). It allows to pass a delay in CLI, so that event collection starts after a certain time since program launch. How...

I am trying to grok what myApp is very busy with (90% cpu single thread). It is a server that i shouldn't restart. I've collected samples by perf record -p 5068 -F 99 --call-graph dwarf sleep 10 A...

I am running a C++ benchmark test for a specific application. In this test, I open the performance counter file (__NR_perf_event_open syscall) before the critical section, proceed with the section ...

I run the following program which call perf_event_open syscall in: Linux sama-desktop 3.18.0-20-rpi2 #21-Ubuntu SMP PREEMPT Sun Apr 5 01:56:02 UTC 2015 armv7l armv7l armv7l GNU/Linux The program: ...

I want to compile pref for android device and i did that base on the guide the guide. One i set NDK environment use Android NDK r9 export NDK_TOOLCHAIN=${NDK}/toolchains/arm-linux-androideabi-4.6/...

In backtraces produced by perf record --call-graph dwarf and printed by perf script, I am consistently getting wrong addresses for maybe 5% of call stacks, i.e. unwinding fails. One example is my_b...

I have a C++ test program that keeps the CPU busy: #include <cstdint> #include <iostream> // Linear-feedback shift register uint64_t lfsr1(uint64_t max_ix) { uint64_t start_state = 0x...

From a great answer on here, my understanding is that perf samples every time an event counter exceeds a threshold. When asked to sample at a certain frequency, it tries to set the event counter th...

Sampling cpu-cycles with perf record is useful for finding optimization candidates if core-utilization is roughly constant. But for code that has multiple phases differing in parallelism counting c...

I used the following command to extract backtraces leading to user level L3-misses in a simple evince benchmark: sudo perf record -d --call-graph dwarf -c 10000 -e mem_load_uops_retired.l3_miss:up...

I tried to use perf stat with LD_PRELOAD as prefix for executable such as: perf stat LD_PRELOAD=$PWD/../user/preload.so ./write 1 It seems not work for perf, are there any way to achieve it?