Simple CPU hogging tool for testing purposes
The build system for cpuhog is a trivial Makefile, so you can build it as follows:
dk@fedora 16:46:23 ~/git/cpuhog $ [0] make
gcc -Wall -Wextra -lpthread cpuhog.c -o cpuhog
dk@fedora 16:46:28 ~/git/cpuhog $ [0]
If you run it without arguments, it will create a CPU hogging thread per each available CPU core and will run infinitely.
dk@fedora 16:48:03 ~/git/cpuhog $ [0] ./cpuhog
^C
dk@fedora 16:48:14 ~/git/cpuhog $ [130]
You can also use environment variables to change cpuhog behavior
- CPUHOG_DEBUG - if set, enables debug logging
- CPUHOG_DURATION - if set, defines the duration of the execution in seconds
- CPUHOG_SYSCALL - if set, forces cpuhog to do a syscall at each iteration of tight loop (gettid is used now)
The example below demonstrates the use of environment variables.
dk@fedora 16:50:13 ~/git/cpuhog $ [0] CPUHOG_DURATION=3 CPUHOG_DEBUG=1 ./cpuhog
Detected 2 available CPU cores
CPU hog thread 1 started
CPU hog thread 0 started
Affined CPU hog thread 0 to CPU core
Changed CPU hog thread 0 name to cpuhog00000
Affined CPU hog thread 1 to CPU core
Changed CPU hog thread 1 name to cpuhog00001
Got signal 14, exiting.
dk@fedora 16:50:25 ~/git/cpuhog $ [0]
While cpuhog is running, you can run top -H to see its threads consuming the CPU.
top - 16:58:56 up 1:28, 1 user, load average: 0.31, 0.13, 0.10
Threads: 148 total, 3 running, 96 sleeping, 0 stopped, 0 zombie
%Cpu(s): 99.3 us, 0.2 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 0.4 si, 0.0 st
KiB Mem : 4039212 total, 3003676 free, 236504 used, 799032 buff/cache
KiB Swap: 4177916 total, 4177916 free, 0 used. 3511692 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
381 dk 20 0 22972 776 696 R 99.9 0.0 0:08.28 cpuhog00000
382 dk 20 0 22972 776 696 R 99.9 0.0 0:08.28 cpuhog00001
1070 dk 20 0 25748 4144 2928 S 0.3 0.1 0:01.70 tmux: server
1 root 20 0 223740 11528 8156 S 0.0 0.3 0:01.70 systemd
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