cd /tmp/
wget https://github.com/jemalloc/jemalloc/archive/5.2.1.tar.gz

yum groupinstall -y 'Development Tools'
tar -xzvf 5.2.1.tar.gz
cd jemalloc-5.2.1
sh ./autogen.sh
./configure --prefix=/usr/
make -j 8
make install

通过上述命令安装完jemalloc.so后，在mysql配置文件my.cnf中添加如下配置

my.cnf配置

[mysql_safe]
malloc-lib=/usr/lib/libjemalloc.so

　　启动mysql