Exercise 6

Implement two scripts: mtxtime.d and mtxtimd.stp that would compute delay between attempt to acquire a userspace mutex and a moment when mutex is acquired. Group times by user stacks and print data as logarithmic histograms.

Use pthread experiment to demonstrate your scripts, like in previous section, TSLoad workload generator itself would be an object in the experiment. Try to identify mutexes that show delays larger than 1 ms.


To prevent problems with symbol resolving in DTrace after tracing process finishes, you can attach to a function experiment_unconfigure() from tsexperiment to print gathered data.