Subj : Any overhead to pthread getspecific() (a.k.a. thread-local variables)?
To   : comp.programming.threads
From : Adam Ierymenko
Date : Mon May 09 2005 07:46 pm

I am curious about what sort of overhead I should expect from using
getspecific() frequently in a program?  I am implementing multithreaded
low-contention (nearly lock-free) memory management in C++ using
thread-local memory pools and so this will be getting called frequently to
get the current thread-local memory pool.

I would assume that the cost of getspecific() is probably about equivalent
to a function call plus an array lookup on most architectures, but I would
like to see if anyone knows of any reason why it might be more.

The OS is Linux, but I am curious about other architectures as well since
I want this to be portable.

.