SIGNALTEST(8)

✨ SIGNALTEST(8) ✨

okay bestie, come SIT. it's signaltest, it lives in the System Manager's Manual, and it's literally the signal roundtrip test software. yes. that one. 🎀

quick housekeeping before we get into it: this whole page is licensed <code>SPDX-License-Identifier: GPL-2.0-only</code> 💅

🌸 NAME 🌸

signaltest — signal roundtrip test software

ngl the name is doing exactly what it says on the tin. no notes. 🫶

🎀 SYNOPSIS 🎀

signaltest [ -a|--affinity NUM] [ -b|--backtrace USEC ] [-D|--duration
TIME] [-h|--help] [--json FILENAME] [-l|--loops LOOPS ] [-p|--prio PRIO]
[-q|--quiet] [-S|--smp] [-t|--threads NUM] [-m|--mlockall ]
[-v|--verbose ]

🦋 OPTIONS 🦋

so these programs are very much "usual GNU command line syntax" girlies — long options start with two dashes (--). the way that's just the vibe. ✨

• -a, --affinity[=PROC-SET] — runs the threads on the set of processors you give it in PROC-SET. if you don't specify PROC-SET, then all processors get used. the threads get assigned to the processors in the set in numeric order, round-robin style. 🎠
  • you can write the processor set as A,B,C, or A-C, or A-B,D-F, and so on*. and the ! character can negate a set — so like, !B-D means use every available CPU except B through D. the cpu numbers are the same ones shown in the processor field in /proc/cpuinfo. see numa(3) for more info on specifying CPU sets.
  • * heads up: support for CPU sets needs libnuma version >= 2. for libnuma v1, PROC-SET, if you specify it, has to be a single CPU number. no ranges, no combos. periodt.
• -b, --breaktrace=USEC — send the break trace command when latency > USEC 🚨
• -D, --duration=TIME — pick how long the test run goes for. append 'm', 'h', or 'd' to say minutes, hours, or days. ⏰
• --help — display usage information 🙋‍♀️
• --json=FILENAME — write the final results into FILENAME, JSON formatted. 📄✨
• -l, --loops=LOOPS — number of loops: default=0 (endless) ♾️
• -p, --priority=PRIO — priority of the highest priority thread 👑
• -q, --quiet — print a summary only on exit 🤫
• -S, --smp — sets options for standard testing on SMP systems. equivalent to using the options: "-t -a", and also keeps any specified priority equal across all threads. 🧠
• -t, --threads=NUM — number of threads: default=2 🧵🧵
• -m, --mlockall — lock current and future memory allocations 🔒
• -v, --verbose — output values on stdout for statistics, format: n:c:v where n=tasknum, c=count, v=value in us 📊

💜 AUTHOR 💜

signaltest was written by <b>Thomas Gleixner</b> <code>&lt;tglx@linuxtronix.de&gt;</code>. icon behavior, honestly. 👑

this manual page was originally written by <b>John Kacur</b> <code>&lt;jkacur@redhat.com&gt;</code> 🫶

copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. this file is offered as-is, without any warranty.

okay that's the whole thing, bestie!! go forth and roundtrip some signals 🌈💖

— this lil transmission was brought to you by <b>November 15, 2020</b>, and yes, it's SIGNALTEST(8), mwah 💋