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Is there a benchmark program I can use to measure random read speeds of a vps without interference from the kernel cache? Also looking for something where you can change the read sizes say 4k-64k.

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up vote 4 down vote accepted

I would recommend using iozone and/or bonnie++ to benchmark. If you're solid on what you need to test, both tools are customizable to those requirements.

For iozone, try something like the following to run a single-threaded random read/write test with a 4k record size using a 4 Gigabyte file.

Run this from the directory you wish to test: iozone -t1 -i2 -r4k -s4g

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I tried running iozone but I keep getting "iozone.DUMMY.0: No such file or directory". Do you know how to fix this error? – incognito2 Aug 13 '11 at 16:09
Make sure you are running iozone in a directory that you have write permissions to. – ewwhite Aug 13 '11 at 16:20
I get the same error as @incognito2. I'm running iozone from my desktop folder which I definitely have write permissions for. – Zero3 Mar 25 at 19:09

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