1f08c3bdfSopenharmony_ciUSAGE 2f08c3bdfSopenharmony_ci 3f08c3bdfSopenharmony_ciSee the program's usage statement by invoking with --help. 4f08c3bdfSopenharmony_ci 5f08c3bdfSopenharmony_ciNOTES 6f08c3bdfSopenharmony_ci 7f08c3bdfSopenharmony_ciThis program works really well for me, but it might not have some of the 8f08c3bdfSopenharmony_cifeatures that you want. If you would like, please extend the code and send 9f08c3bdfSopenharmony_cime the patch[1]. Enjoy the program :-) 10f08c3bdfSopenharmony_ci 11f08c3bdfSopenharmony_ciPlease use the context diff format. That is: save the original program 12f08c3bdfSopenharmony_cias stress.c.orig, then make and test your desired changes to stress.c, then 13f08c3bdfSopenharmony_cirun 'diff -u stress.c.orig stress.c' to produce a context patch. Thanks. 14f08c3bdfSopenharmony_ci 15f08c3bdfSopenharmony_ciAmos Waterland <apw@rossby.metr.ou.edu> 16f08c3bdfSopenharmony_ciNorman, Oklahoma 17f08c3bdfSopenharmony_ci27 Nov 2001 18f08c3bdfSopenharmony_ci 19f08c3bdfSopenharmony_ciEXAMPLES 20f08c3bdfSopenharmony_ci[examples] 21f08c3bdfSopenharmony_ci 22f08c3bdfSopenharmony_ciThe simple case is that you just want to bring the system load average up to 23f08c3bdfSopenharmony_cian arbitrary value. The following forks 13 processes, each of which spins 24f08c3bdfSopenharmony_ciin a tight loop calculating the sqrt() of a random number acquired with 25f08c3bdfSopenharmony_cirand(). 26f08c3bdfSopenharmony_ci 27f08c3bdfSopenharmony_ci % stress -c 13 28f08c3bdfSopenharmony_ci 29f08c3bdfSopenharmony_ciLong options are supported, as well as is making the output less verbose. 30f08c3bdfSopenharmony_ciThe following forks 1024 processes, and only reports error messages if any. 31f08c3bdfSopenharmony_ci 32f08c3bdfSopenharmony_ci % stress --quiet --hogcpu 1k 33f08c3bdfSopenharmony_ci 34f08c3bdfSopenharmony_ciTo see how your system performs when it is I/O bound, use the -i switch. 35f08c3bdfSopenharmony_ciThe following forks 4 processes, each of which spins in a tight loop calling 36f08c3bdfSopenharmony_cisync(), which is a system call that flushes memory buffers to disk. 37f08c3bdfSopenharmony_ci 38f08c3bdfSopenharmony_ci % stress -i 4 39f08c3bdfSopenharmony_ci 40f08c3bdfSopenharmony_ciMultiple hogs may be combined on the same command line. The following does 41f08c3bdfSopenharmony_cieverything the preceding examples did in one command, but also turns up the 42f08c3bdfSopenharmony_civerbosity level as well as showing how to cause the command to 43f08c3bdfSopenharmony_ciself-terminate after 1 minute. 44f08c3bdfSopenharmony_ci 45f08c3bdfSopenharmony_ci % stress -c 13 -i 4 --verbose --timeout 1m 46f08c3bdfSopenharmony_ci 47f08c3bdfSopenharmony_ciAn value of 0 normally denotes infinity. The following is how to do a fork 48f08c3bdfSopenharmony_cibomb (be careful with this). 49f08c3bdfSopenharmony_ci 50f08c3bdfSopenharmony_ci % stress -c 0 51f08c3bdfSopenharmony_ci 52f08c3bdfSopenharmony_ciFor the -m and -d options, a value of 0 means to redo their operation an 53f08c3bdfSopenharmony_ciinfinite number of times. To allocate and free 128MB in a redo loop use the 54f08c3bdfSopenharmony_cifollowing command. This can be useful for "bouncing" against the system RAM 55f08c3bdfSopenharmony_ciceiling. 56f08c3bdfSopenharmony_ci 57f08c3bdfSopenharmony_ci % stress -m 0 --hogvm-bytes 128M 58f08c3bdfSopenharmony_ci 59f08c3bdfSopenharmony_ciFor the -m and -d options, a negative value of n means to redo the operation 60f08c3bdfSopenharmony_ciabs(n) times. Here is now to allocate and free 5MB three times in a row. 61f08c3bdfSopenharmony_ci 62f08c3bdfSopenharmony_ci % stress -m -3 --hogvm-bytes 5m 63f08c3bdfSopenharmony_ci 64f08c3bdfSopenharmony_ciYou can write a file of arbitrary length to disk. The file is created with 65f08c3bdfSopenharmony_cimkstemp() in the current directory, the default is to unlink it, but 66f08c3bdfSopenharmony_ciunlinking can be overridden with the --hoghdd-noclean flag. 67f08c3bdfSopenharmony_ci 68f08c3bdfSopenharmony_ci % stress -d 1 --hoghdd-noclean --hoghdd-bytes 13 69f08c3bdfSopenharmony_ci 70f08c3bdfSopenharmony_ciLarge file support is enabled. 71f08c3bdfSopenharmony_ci 72f08c3bdfSopenharmony_ci % stress -d 1 --hoghdd-noclean --hoghdd-bytes 3G 73