Software: Apache. PHP/7.3.33 

uname -a: Linux web25.us.cloudlogin.co 5.10.237-xeon-hst #1 SMP Mon May 5 15:10:04 UTC 2025 x86_64 

uid=233359(alpastrology) gid=888(tty) groups=888(tty),33(tape) 

Safe-mode: OFF (not secure)

/usr/share/doc/perf-tip/   drwxr-xr-x
Free 6182.15 GB of 6263.36 GB (98.7%)
                            Encoder    Tools    Proc.    FTP brute    Sec.    SQL    PHP-code    Update    Feedback    Self remove    Logout    

Viewing file:     tips.txt (2.81 KB)      -rw-r--r--

For a higher level overview, try: perf report --sort comm,dso
Sample related events with: perf record -e '{cycles,instructions}:S'
Compare performance results with: perf diff [<old file> <new file>]
Boolean options have negative forms, e.g.: perf report --no-children
Customize output of perf script with: perf script -F event,ip,sym
Generate a script for your data: perf script -g <lang>
Save output of perf stat using: perf stat record <target workload>
Create an archive with symtabs to analyse on other machine: perf archive
Search options using a keyword: perf report -h <keyword>
Use parent filter to see specific call path: perf report -p <regex>
List events using substring match: perf list <keyword>
To see list of saved events and attributes: perf evlist -v
Use --symfs <dir> if your symbol files are in non-standard locations
To see callchains in a more compact form: perf report -g folded
Show individual samples with: perf script
Limit to show entries above 5% only: perf report --percent-limit 5
Profiling branch (mis)predictions with: perf record -b / perf report
To show assembler sample contexts use perf record -b / perf script -F +brstackinsn --xed
Treat branches as callchains: perf report --branch-history
To count events in every 1000 msec: perf stat -I 1000
Print event counts in CSV format with: perf stat -x,
If you have debuginfo enabled, try: perf report -s sym,srcline
For memory address profiling, try: perf mem record / perf mem report
For tracepoint events, try: perf report -s trace_fields
To record callchains for each sample: perf record -g
To record every process run by a user: perf record -u <user>
Skip collecting build-id when recording: perf record -B
To change sampling frequency to 100 Hz: perf record -F 100
See assembly instructions with percentage: perf annotate <symbol>
If you prefer Intel style assembly, try: perf annotate -M intel
For hierarchical output, try: perf report --hierarchy
Order by the overhead of source file name and line number: perf report -s srcline
System-wide collection from all CPUs: perf record -a
Show current config key-value pairs: perf config --list
Show user configuration overrides: perf config --user --list
To add Node.js USDT(User-Level Statically Defined Tracing): perf buildid-cache --add `which node`
To report cacheline events from previous recording: perf c2c report
To browse sample contexts use perf report --sample 10 and select in context menu
To separate samples by time use perf report --sort time,overhead,sym
To set sample time separation other than 100ms with --sort time use --time-quantum
Add -I to perf record to sample register values, which will be visible in perf report sample context.
To show IPC for sampling periods use perf record -e '{cycles,instructions}:S' and then browse context
To show context switches in perf report sample context add --switch-events to perf record.