安装 jemalloc for mysql

参考：　MySQL bug：https://bugs.mysql.com/bug.php?id=83047&tdsourcetag=s_pcqq_aiomsg

　　　　https://github.com/jemalloc/jemalloc/blob/dev/INSTALL.md

（1）ptmalloc 是glibc的内存分配管理

（2）tcmalloc 是google的内存分配管理模块

（3）jemalloc 是BSD的提供的内存分配管理 (可以使用jemalloc优化Nginx)

三者jemalloc和tcmalloc的性能不分伯仲，而ptmalloc则要低一些

1、下载最新版jemalloc

git clone https://github.com/jemalloc/jemalloc

cd jemalloc

[root@bogon jemalloc]# cat VERSION
5.1.0-108-gc4063ce439523d382f2dfbbc5bf6da657e6badb0

2、安装步骤：

./autogen.sh

./configure 

make 

make install

[root@bogon jemalloc]# make install

/usr/bin/install -c -d /usr/bin
/usr/bin/install -c -m 755 bin/jemalloc-config /usr/bin
/usr/bin/install -c -m 755 bin/jemalloc.sh /usr/bin
/usr/bin/install -c -m 755 bin/jeprof /usr/bin
/usr/bin/install -c -d /usr/include/jemalloc
/usr/bin/install -c -m 644 include/jemalloc/jemalloc.h /usr/include/jemalloc
/usr/bin/install -c -d /usr/lib
/usr/bin/install -c -m 755 lib/libjemalloc.so.2 /usr/lib
ln -sf libjemalloc.so.2 /usr/lib/libjemalloc.so
/usr/bin/install -c -d /usr/lib
/usr/bin/install -c -m 755 lib/libjemalloc.a /usr/lib
/usr/bin/install -c -m 755 lib/libjemalloc_pic.a /usr/lib
/usr/bin/install -c -d /usr/lib/pkgconfig
/usr/bin/install -c -m 644 jemalloc.pc /usr/lib/pkgconfig
/usr/bin/install -c -d /usr/share/doc/jemalloc
/usr/bin/install -c -m 644 doc/jemalloc.html /usr/share/doc/jemalloc
/usr/bin/install: cannot stat ‘doc/jemalloc.html’: No such file or directory
make: *** [install_doc_html] Error 1
[root@bogon jemalloc]#

默认安装目录：

PREFIX             : /usr/local
BINDIR             : /usr/local/bin
DATADIR            : /usr/local/share
INCLUDEDIR         : /usr/local/include
LIBDIR             : /usr/local/lib
MANDIR             : /usr/local/share/man

3、配置mysqld使用jemalloc，需要将配置写到[mysqld_safe] section

[mysqld_safe]
malloc-lib=/usr/local/lib/libjemalloc.so

4. 如果直接使用sqld启动，

export LD_PRELOAD=/usr/local/lib/libjemalloc.so

然后启动sqld

5、查看jemalloc是否生效

lsof -n |grep jemalloc

[root@localhost mysql3306]# lsof -n |grep jemalloc
bash      11223                 root  cwd       DIR              253,0      4096      35178 /software/jemalloc
mysqld    17475                mysql  mem       REG              253,0   4291512   18480172 /usr/lib/libjemalloc.so.2
mysqld    17475 17482          mysql  mem       REG              253,0   4291512   18480172 /usr/lib/libjemalloc.so.2
mysqld    17475 17483          mysql  mem       REG              253,0   4291512   18480172 /usr/lib/libjemalloc.so.2
mysqld    17475 17484          mysql  mem       REG              253,0   4291512   18480172 /usr/lib/libjemalloc.so.2

显示以上信息说明mysql已经成功加载jemalloc