associative array synchronization question

[Josh Stone]

On 07/20/2012 01:37 PM, Nicholas Murphy wrote:
> What does it mean that you "sometimes" fail to take a lock?  Do you
> just skip executing the probe if you determine that you can't get the
> lock?

The only failure is from contention.  We will spin-and-wait for a lock
to free up for a small time, but if it's too busy on other cpus, we'll
eventually give up.  That's "sometimes", but hopefully rare. :)

And yes, if we can't get all necessary locks, that probe handler will be
skipped altogether.

You can find a bit more about this on the wiki:
http://sourceware.org/systemtap/wiki/TipSkippedProbesOptimization

Josh