TCMalloc

TCMalloc (google-perftools) 是用于优化C++写的多线程应用，比glibc 2.3的malloc快。这个模块可以用来让MySQL在高并发下内存占用更加稳定。

安装步骤：

The glibc built-in stack-unwinder on 64-bit systems has some problems with the perftools libraries. (In particular, the cpu/heap profiler may be in the middle of malloc, holding some malloc-related locks when they invoke the stack unwinder. The built-in stack unwinder may call malloc recursively, which may require the thread to acquire a lock it already holds: deadlock.)

For that reason, if you use a 64-bit system, we strongly recommend you install libunwind before trying to configure or install gperftools. libunwind can be found at

http://download.savannah.gnu.org/releases/libunwind/libunwind-0.99-beta.tar.gz

Even if you already have libunwind installed, you should check the version. Versions older than this will not work properly; too-new versions introduce new code that does not work well with perftools (because libunwind can call malloc, which will lead to deadlock).

# wget http://download.savannah.gnu.org/releases/libunwind/libunwind-0.99-beta.tar.gz 
# tar xvf libunwind-0.99-beta.tar.gz 
# cd libunwind 
# ./configure 
# make && make install

# wget https://gperftools.googlecode.com/files/gperftools-2.0.tar.gz 
# tar xvf gperftools-2.0.tar.gz 
# cd gperftools 
# ./configure 
# make && make install

修改配置文件：

打开mysqld_safe脚本 (默认在/usr/bin/mysqld_safe)

在此脚本文件开始加入

LD_PRELOAD="/usr/local/lib/libtcmalloc.so"

# service mysql restart