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I'm in search of a filesystem benchmark utility. I basically want to run a test which should be able to do random reads/writes on a specified drive with a given block size. e.g. a 4K random write on a linux system.

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Were you ever able to track down a utility which did what you wanted it to do? – irrational John May 31 '12 at 18:05

Check the Linux Benchmark Suite page. It has links to a bunch of benchmarks, including bonie and bonie++ which can do what you want (and more).

For bonnie++, to change the block size, you might also need to specify the test file size.

usage: bonnie++ [-d scratch-dir] [-s size(MiB)[:chunk-size(b)]]

So bonnie++ ... -s 1g:4k ... should do I/O in 4096 byte chunks.

Also check out iozone. It has a scary number of command line arguments, but r can be used to fix the block size. Check out the documentation to understand the output.

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Thanks for your reply but neither bonnie nor the programms on the Linux Benchmark Suite (been there, done that) are able to do random write/reads with 4K Chunk size. I found IOtest, which is exactly what I'm looking for, unfortunately there is no working download link on the company's page. – thpetrus Aug 5 '11 at 9:20
I was pretty sure it could. Did you try the -s size:chunk-size option? – Mat Aug 5 '11 at 11:31
Thanks again! Yes, I tried bonnie++ with the chunk-size and this is the output: dpaste.com/587091 As you can see, it only displays random create per second and delete per second. I'm looking for a tool with a output like this: lwn.net/Articles/220277 – thpetrus Aug 5 '11 at 11:55

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