#include <perf/mmap.h> #include "event.h" #include "evlist.h" #include "evsel.h" #include "debug.h" #include "record.h" #include "tests.h" #include "util/mmap.h" #include "util/sample.h" #include "util/cpumap.h" · static int sched__get_first_possible_cpu(pid_t pid, cpu_set_t *maskp) { int i, cpu = -1; int nrcpus = cpu__max_cpu().cpu; size_t size = CPU_ALLOC_SIZE(nrcpus); ·

Record build-id of all DSOs regardless whether it's actually hit or not. ... Use <n> control blocks in asynchronous (Posix AIO) trace writing mode (default: 1, max: 4). Asynchronous mode is supported only when linking Perf tool with libc library

January 17, 2021 - Record "perf" performance metrics for individual functions/regions of an ELF binary. - zyedidia/perforator

The perf tool can be used to collect profiles on per-thread, per-process and per-cpu basis. There are several commands associated with sampling: record, report, annotate. You must first collect the samples using perf record. This generates an output file called perf.data.

# Listing all currently known events: perf list # CPU counter statistics for the entire system, for 5 seconds: perf stat -a sleep 5 # Count ext4 events for the entire system, for 10 seconds: perf stat -e 'ext4:*' -a sleep 10 # Show system calls by process, refreshing every 2 seconds: perf top -e raw_syscalls:sys_enter -ns comm # Sample CPU stack traces for the specified PID, at 99 Hertz, for 10 seconds: perf record -F 99 -p PID -g -- sleep 10 # Sample CPU stack traces for the entire system, at 99 Hertz, for 10 seconds: perf record -F 99 -ag -- sleep 10 # Sample CPUs at 49 Hertz, and show top addresses and symbols, live (no perf.data): perf top -F 49 # Show perf.data in an ncurses browser (TUI) if possible: perf report # Show perf.data file as a text report with a sample count column: perf report -n --stdi # List all raw events from perf.data: perf script

perf record --call-graph lbr -F 100 ./program args perf script report flamegraph

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Lightweight recording and sampling of performance counters for specific code segments directly from your C++ application. - jmuehlig/perf-cpp

If the input filename does not have any extension, _perf.tsv will be appended to the filename. Please note that even in the case of no identified SSRs, the output file is still created (therefore overwriting any previous file of the same name) but with no content in the file. The output is a tab-delimited file, with one SSR record ...

To do off-CPU analysis with Hotspot, you need to record the data with a very specific command: perf record \ -e cycles \ # on-CPU profiling -e sched:sched_switch --switch-events \ # off-CPU profiling --sample-cpu \ # track on which core code is executed -m 8M \ # reduce chance of event loss --aio -z \ # reduce disk-I/O overhead and data size --call-graph dwarf \ # we definitely want backtraces <your application>

Use Kconfig to allow selecting features and build minimal version of perf, e.g. one with just 'record' for use in embedded platforms.

perf_events is part of the Linux kernel, under tools/perf. While it uses many Linux tracing features, some are not yet exposed via the perf command, and need to be used via the ftrace interface instead. My perf-tools collection (github) uses both perf_events and ftrace as needed.

$ sudo perf record -a -e sched:sched_switch -e sched:sched_waking \ -e sched:sched_pi_setprio -e sched:sched_process_fork -e sched:sched_process_exit \ -e sched:sched_process_free -e sched:sched_wakeup \ -e irq:softirq_entry -e irq:softirq_raise -e irq:softirq_exit \ -e irq:irq_handler_entry -e irq:irq_handler_exit \ -e block:block_rq_complete -e block:block_rq_insert -e block:block_rq_issue \ -e block:block_bio_frontmerge -e power:cpu_frequency \ -e net:net_dev_queue -e net:netif_receive_skb \ -e timer:hrtimer_start -e timer:hrtimer_cancel -e timer:hrtimer_expire_entry -e timer:hrtimer_expire_exit \ -e syscalls:sys_enter_* -e syscalls:sys_exit_* \ wget https://lttng.org

record stats for running process -o <file> .............. write output to file (default perf.data) -F <hz> ................ sampling frequency --call-graph <method> ..

perf record -- node --perf-basic-prof --print-code --redirect-code-traces /tmp/fib.js perf report --objdump=$HOME/src/chr/v8/tools/objdump-v8

* perf top, perf record, perf report, etc.) are started. */ #include "builtin.h" #include "perf.h" · #include "util/build-id.h" #include "util/cache.h" #include "util/env.h" #include <internal/lib.h> // page_size ·

This repository provides a Linux kernel bootable on RISC-V boards from SiFive - RISC-V-Linux/linux/tools/perf/Documentation/perf-record.txt at master · westerndigitalcorporation/RISC-V-Linux

To isolate profiling to a single process or program use perf record.

$ perf record -e cycles:u -g -- ./node benchmark/http_simple.js

lbr/ -- functionality for processing Last Branch Record (LBR) streams ... mmm/ -- the matrix-matrix mutiply (mmm) HPC kernel - multiple optimizations as demonstrated in Tuning Performance via Metrics with Expectations