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I'm running badblocks -vws /dev/sda on a new 80GB laptop drive to make sure the disk is good. So far it's completed 2 passes and is working on it's third.

How many passes does it normally make?

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up vote 0 down vote accepted

If the only flags you ran the command with were -v, -w and -s, then it should have exited after the first pass. Seeing as you're performing a with-write test, it should be safe to ^C out of anytime.

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badblocks -swv, at least the version I've got (from e2fsprogs 1.41.11) will run four passes with four different patterns before exiting. – gbroiles Aug 8 '10 at 19:36
    
@gbroiles That isn't four passes, it's a single pass with four patterns. That might seem pedantic, but the difference is relevant when considering the -t and -p options. See my answer. – Jon Bentley May 5 '15 at 7:40

What you're seeing is not multiple passes, it's multiple test patterns within a single pass. The -w option runs a single pass by default, and you can specify additional passes with the -p option.

However, a single pass with the -w option tests four different patterns: 0xaa, 0x55, 0xff, 0x00.

You can override this with the -t option, to specifiy your own test pattern(s). E.g. to test only a single pattern you could do something like this:

badblocks -vwst 0x00 /dev/sda

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