The Google Perftools, especially tcmalloc (Thread Caching Malloc), can be very useful to speed up your applications, depending on your environment :
TCMalloc is faster than the glibc 2.3 malloc (available as a separate library called ptmalloc2) and other mallocs that I have tested. ptmalloc2 takes approximately 300 nanoseconds to execute a malloc/free pair on a 2.8 GHz P4 (for small objects). The TCMalloc implementation takes approximately 50 nanoseconds for the same operation pair.
Its deployment in your LAMP stack can speed up your MySQL servers, since it enhances memory allocation on threaded applications with the downside of larger memory footprints.
Here is how to use it easily…
Installation
First of all, be sure you use Debian 5.0 (a.k.a. “Lenny”) or later. Then install the minimal tcmalloc library from Dotdeb :
apt-get install libtcmalloc-minimal0 |
apt-get install libtcmalloc-minimal0
Then, since the mainstream MySQL packages are not compiled against tcmalloc, you’ll have to trick your OS’ dynamic linker by adding the following line at the top of your /etc/init.d/mysql init script :
export LD_PRELOAD="/usr/lib/libtcmalloc_minimal.so.0" |
export LD_PRELOAD="/usr/lib/libtcmalloc_minimal.so.0"
After relauching your MySQL server using the modified init script, you’ll take profit from tcmalloc’s faster memory allocation.
Results
At the time of writing this article, I didn’t make benchmarks, but some reported that they had a ~15-20% performance gain. Please leave comments about your experience.