While installing Percona Server 5.5/5.6 on Ubuntu 13.04/13.10, I got some weird errors, which I never faced before. Errors were something like,

dpkg: error processing /var/cache/apt/archives/libmysqlclient18_1%3a5.5.35-rel33.0-611.raring_amd64.deb (–unpack):
  libmysqlclient18:amd64 1:5.5.35-rel33.0-611.raring (Multi-Arch: no) is not co-installable with libmysqlclient18 which has multiple installed instances

shell>  sudo apt-get install percona-server-server-5.5
 Reading package lists... Done
 Building dependency tree
 Reading state information... Done
 The following extra packages will be installed:
 libdbd-mysql-perl libmysqlclient18 percona-server-client-5.5 percona-server-common-5.5
 Suggested packages:
 tinyca
 The following NEW packages will be installed:
 libdbd-mysql-perl libmysqlclient18 percona-server-client-5.5 percona-server-common-5.5 percona-server-server-5.5
 0 …

I write this post over to have a quick access to this tutorial than to promote the blog. The problem For Several times this has happened to me, always install a new server, or personal machine. I install mysql ,… Continue Reading →

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Since MySQL Workbench 6.0 isn’t available for Fedora, Version 20, I’m having my students install it on their local Windows and Mac OS X operating systems. You can configure the /etc/sysconfig/iptables file to enable port 3306 after installing MySQL on Fedora.

You can open a port by adding the following line to the /etc/sysconfig/iptables file (Fedora’s instructions on editing iptables). The file won’t exist initially, but you can create it by running the following command as the root superuser or sudoer:

shell> service iptables save

You you can run the following commands as the root superuser, …

When looking back at 2013, one of the things that really stand out is what we’ve done with MySQL in Linux distros. At least it stands out to me, but for most people it’s probably the janitorial work that they never notice as long as everything keeps working perfectly. Although invisible to most, this is the important work that makes it possible for all Linux users to run MySQL.

Most distros are maintained by volunteers doing packaging work in their spare time, and we as software developers should be very grateful for all the work and effort they put into distributing our software (for free!). I know we at Oracle are!

We’ve had a distro-like project of our own in 2013. We have created our own repositories for various Linux distros (I hope to see more in the future), so that users that want the latest and greatest can get that even if their …

There is a good article over at Re-Code by ex-Microsoft VP Steven Sinofsky called "The Four Stages of Disruption".  It describes the evolution of products and markets through disruption, drawing from Sinofsky's own insights and also building on the work of Everett Rogers ("The Diffusion of Innovations") and Clayton Christensen ("The …

There is much more to write about all the work we do at Facebook with memory management efficiency on our systems, but there was this one detour investigation in the middle of 2012 that I had to revisit recently courtesy of Wikipedia.

There are lots of factors that make machines page out memory segments into disk, thus slowing everything down and locking software up – from file system cache pressure to runaway memory leaks to kernel drivers being greedy. But certain swap-out scenarios are confusing – systems seem to have lots of memory available, with proper settings file system cache should not cause swapping, and obviously in production environment all the memory leaks are ironed out.

And yet in mid-2012 we noticed that our new kernel machines were swapping out for no obvious reason. When it comes to swapping, MySQL community will always point to Jeremy’s post on …

I was busy testing a PXC cluster today when suddenly was buffled with a confusing error:

140108 23:33:39 innobackupex: Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup' (using password: NO).
innobackupex: Error: Failed to connect to MySQL server as DBD::mysql module is not installed at /usr/bin/innobackupex line 2913.

OK, so my first though was DBD::mysql is missing, but as I checked:

[root@pxc03 keepalived]# yum list installed| grep perl-DBD-MySQL
perl-DBD-MySQL.x86_64 4.013-3.el6 @base

After some digging, it’s not actually the module that is missing – it was one of the module’s dependency which is the mysql client library.

[root@pxc03 keepalived]# yum deplist perl-DBD-MySQL.x86_64|grep mysql
dependency: libmysqlclient.so.16()(64bit)
provider: mysql-libs.x86_64 5.1.71-1.el6
dependency: libmysqlclient.so.16(libmysqlclient_16)(64bit)
provider: mysql-libs.x86_64 …

I built a new image on VMWare Fusion for my class, which required installing MySQL 5.6 on Fedora, Version 20. If you don’t know how to add your user to the sudoers list, you should check this older and recently updated blog post.

1. Download the MySQL Yum Repository and launch the downloaded RPM.

1. Install MySQL on Fedora, Version 20, which you can find with the following command:

shell> rpm -qa | grep mysql
mysql-community-release-fc20-5.noarch

The fc20-5 changes with point releases, but assuming that you’re installing the fc20-5 release:

      shell> sudo yum localinstall …

In short, during an optimization or a MySQL query involving a lot of replace(replace(replace…))) I decided to compile PREG as lib_mysqludf_preg from UDF Repository for MySQL in a view to use PCRE functions directly in MySQL.

Too bad MySQL still cant not use functions for index creation, but this is not the theme of this post.

So, fist install MariaDB 10.0.6:
set the MariaDB 10.0.6 repo, I used the ftp mirror at ftp.ulak.net.tr

root@seik-centos-01:[Wed Dec 18 23:55:12][/tmp]$ cat /etc/yum.repos.d/MariaDB.repo 
# MariaDB 10.0 CentOS repository list - created 2013-12-18 18:07 UTC
# http://mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
#baseurl = http://yum.mariadb.org/10.0/centos6-amd64
baseurl = ftp://ftp.ulak.net.tr/pub/MariaDB/mariadb-10.0.6/yum/centos6-amd64/
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1 …

Because most MySQL production systems probably run on Linux, I’ve decided to place the most important Linux tuning tips that will help improve MySQL performance. There is nothing new here, most of them are well known, however, I’ve decided to collect those Linux configuration tips into 1 blog post.

Filesystem

• ext4 (or xfs), mount with noatime
• Scheduler – use deadline or noop

# echo deadline >/sys/block/sda/queue/scheduler
add "elevator=deadline" to grub.conf

(For more info see Linux Schedulers in TPCC like benchmark)

Memory

• Swappiness and NUMA:

# echo 0 > /proc/sys/vm/swappiness
add "vm.swappiness = 0" to /etc/sysctl.conf

• Set numa interleave all

numactl …