how to generate HDD I/O?

[mpugach]

Hello,

I need a tool to generate HDD workload and monitor errors.

The main task is to test high availability schemes with SAN switches.

Can anyone help me?

[Torsten. · Accepted solution]

You could read with "dd" from the disk device.

[Turgay Cavdar]

If there is a file system, you can also use prealloc command:

# prealloc file_name 5000000000

[George_Dodds]

dd would do it

dd if=/dev/rdsk/c1t0d0 of=/dev/null bs=1024k

[Steven E. Protter]

Shalom,

I'd run a couple of dd commands varying block sizes. That will be fine for testing hd performance.

SEP

[Dennis Handly]

>I'd run a couple of dd commands varying block sizes.

These would be testing sequential I/O.  I suppose if you did more than one at the same time, that may be random enough?

[mpugach]

Thank you all. 

dd is fine.

[Bill Hassell]

Attached is diskperf which is a wrapper for dd to make it easier to specify dd parameters. Here are the options:

 # diskperf

Requires MB and at least one DSF
================================

   Usage:  [ -l log ] [ -r KB ] <MB> <DSF> [ more <DSF> ]

   where: MB  = megabytes to read
          DSF = filename (CTD, persistent with partial/full path)

   optional:
         -l log file (fullpath or just device name)
         -r KB (min 1, max 16384)

   Will run a dd read test on the device
   and write the results to the logfile.

Here is a sample output:

# diskperf 300 c8t11d0 c2t2d0
20110723.215130 /dev/rdsk/c8t11d0 (vgbig): 300MB in 5.6 secs (300 recs @ 1024KB) = 53.5MB/sec
20110723.215138 /dev/rdsk/c2t2d0 (vg00): 300MB in 8.2 secs (300 recs @ 1024KB) = 36.5MB/sec

You can start multiple copies of different disks and LUNs for a load generator.

[VK2COT]

Hello,

Other already gave you some good advice. May I add more (it is always good to have choices in your life):

a) Bonnie+

http://www.coker.com.au/bonnie++/

b) IOzone

http://www.iozone.org/

c) IOstone

http://www.acnc.com/benchmarks/iostone.zip

d) IObench

http://www.acnc.com/benchmarks/iobench.tar.Z

e) Bonnie

http://www.acnc.com/benchmarks/bonnie.tar.gz

f) nbench

http://www.tux.org/~mayer/linux/bmark.html

g) Diskbench

http://www.hp.com/go/dspp

h) You could even use Linux Test Project Suite (LTP) and extract various scripts that suit you for HP-UX:

http://ltp.sourceforge.net/

The LTP has over 3,000 tests.

i) If you want a vendor-based tool, and you run HP-UX 11.23 or newer (11.31), then HP offers it as long as you sign an ETD Test Tool Non Disclosure Agreement. It is called Meatgrinder.

j) Also:

http://www.opensourcetesting.org/performance.php

You could do it through many ways, including primitive but efficient scripts.

Finally, a not-so-known tool that is very nice. Some time ago, I was involved in investigating the installation of

GPLv2 workload generator to HP-UX. The source code is here:

http://weather.ou.edu/~apw/projects/stress/

It is designed for POSIX systems, and mostly used on Linux distributions, OpenBSD, and FreeBSD.

Here is how it worked on HP-UX 11.31...

1. Install the following depots (for example, go to Porting and Archiving Centre for HP-UX):

http://hpux.connect.org.uk/

gettext-0.18.1.1-ia64-11.31.depot

libiconv-1.13.1-ia64-11.31.depot

make-3.82-ia64-11.31.depot

texinfo-4.13a-ia64-11.31.depot

zlib-1.2.5-ia64-11.31.depot

gcc-4.2.3-ia64-11.31.depot

2. Set up environment variable CC (I use Posix Shell on my machine, which is HP-UX standard):

# CC=/usr/local/bin/gcc; export CC

No need to change the PATH variable.

3. Run the compilation:

# cd /var/tmp/stress-1.0.4

# ./configure

In any case, you have plenty of choices.

Regards,

VK2COT