Cleanup

[ikiwiki.git] / docs / howtos / HowToStressTest.mdwn

[[!toc levels=3 ]]



## Overview 

Some people may have read about Peter Holms' Stress Test Suite on

commits@, and yes, Matt and I have found several bugs with it.



To get wider testing I thought I could write a little Stress-Test-Suite

guide. :)



## Get the source 

First of all, get the source, it's available at:



http://holm.cc/stress/src/

or

http://people.freebsd.org/~pho/stress/src/



And this is the version I'm using in this guide:



SHA1 (stress2.tgz) = 844faff0b5372cdbcfbfbe66ac769df597c56599



Last modified: 23-May-2006 14:31/18:30



So let's fetch it:



    

    # fetch http://www.holm.cc/stress/src/stress2.tgz





Untar it somewhere and apply this patch:



http://leaf.dragonflybsd.org/~cosmicdj/stress2dfly.patch.gz



SHA1 (stress2dfly.patch.gz) = f0fd1b4290d2bdcfc45862b4279687afac9d2210



    

    # fetch http://leaf.dragonflybsd.org/~cosmicdj/stress2dfly.patch.gz

    # cd stress2; zcat ../stress2dfly.patch.gz | patch -p1





But before you start compiling it you need to tell

stress2/lib/resources.c your swapsize, so start your editor and search

for "const int64_t sz = 524256;". Now you need to replace 524256 with

your swapsize.



How to do that:



    

    # swapinfo -k

    Device 1K-blocks Used Avail Capacity

    /dev/ad0s1b 637704 156 637548 0%

    # echo "637704 / 4" | bc # take the 1K-blocks and devide them by 4

    159426





Replace the (sz =) 524256 in lib/resources.c with this number!



You can compile the suite now:



    

    # cd ../stress2

    # make





One last thing before you can start stressing your machine, edit

default.cfg and change BLASTHOST to an IP with a machine running inetd

with UDP discard enabled. If you don't have such a machine you can set

it to 127.0.0.1 or your local NIC IP and use DragonFly's inetd with



    

    discard dgram udp wait root internal





enabled (uncommented) in /etc/inetd.conf



So what's next?



## Set up your environment, reboot 



First some considerations. You want to stress test your machine?

Your machine could panic and fsck takes quite some time... and

uploading 1+GB crashdump isn't fun, either. So we'll do a reboot!



At the Beasty-bootmenu, select



    

    6. Escape to loader prompt





and at the



    

    ok





prompt we'll first limit the memory DragonFly BSD sees (and thus the

crashdump size) to 256MB



    

    ok set hw.physmem="256M"

    ok





and then we'll boot into single-user mode.



    

    ok boot -s





## Set up your environment, Post-reboot 



The first thing we'll do is:



    

    $ fsck -p





And then we'll mount some important dirs read-only!



    

    $ mount -r /home # this is were the stress-test-suite is

    $ mount -r /usr # you can leave this out but some cmds might come handy

    $ mount /tmp # usualy MFS, if not: mount_mfs -s 262144 swap /tmp

    $ mount /proc # shouldn't hurt...





Then we'll start some services:



    

    $ /etc/rc.d/dumpon start # don't forget to set up a dumpdev in rc.conf

    $ /etc/rc.d/swap1 start # a stress-test needs it

    $ /etc/rc.d/netif start





If you don't have a "blasthost" with UDP discard enabled somewhere in your network,

just start a local inetd:



    

    $ inetd -R 0 -p /tmp/inetd.pid # -R 0 disable rate limiting,

        # needed for the udp stress-test





## How to run the stress-test 



Quoting stress2/README: "Do not run the tests as root."



So let's switch to an ordinary user:



    

    $ su -m ordinary_user

    # cd /home/ordinary_user/stress2

    # setenv INCARNATIONS 10

    # ./run.sh





If you want some verbosity:



    

    # setenv VERBOSE 4

    # ./run.sh





And if you want to run all tests:



    

    # ./run.sh all.cfg





And that's it. If the stress test triggers a panic,

your filesystems are safe because everything is mounted read-only.



## Hints 



If you got a panic, you need to boot with the same

hw.physmem settings, otherwise savecore will not find your crashdump!



## Thanks 

Thanks to Peter Holm (http://www.holm.cc) for his stress test.

Thanks to Matt Dillon and everyone else involved for DragonFly BSD.