What does this dtrace error mean?

Question

When running iotop -C 5 12 on my late-2010 Macbook Pro (10.6.7) I get repeated instances of this error:

dtrace: error on enabled probe ID 5 (ID 19507: io:mach_kernel:buf_strategy:start): illegal operation in action #3 at DIF offset 0

What's the cause of this and how do I fix it?

Answer 1

The errors are getting output to stderr, and can be filtered out by running the command as such:

sudo iotrace -C 5 12 2>/dev/null

This does have the side effect of filtering out any other errors that might come up. I've found it to be an ok tradeoff, in that it's made my iotop output readable.

I'm not sure what the cause of the errors are, unfortunately. I've searched, but have not been able to find anything as of yet.