Scenario Master – Master replication

MasterA is a client facing server
MasterB is a warm standby server (read only)

MasterB restarted abruptly and when instances were braught back up MasterA (it’s slave) was showing the following error:

MasterA has the following error in show slave status:
Last_IO_Errno: 1236
Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: ‘Could not find first log file name in binary log index file’

Solution:

Slave: stop slave;

Master: flush logs
Master: show master status; — take note of the master log file and master log position

Slave: CHANGE MASTER TO MASTER_LOG_FILE=’log-bin.00000X′, MASTER_LOG_POS=106;
Slave: start slave;

MyISAM is the default storage engine in MySQL server. It consists of three types of files: .myi, .frm, and .myd. Of these three, the MYI file is the index file that stores a counter in its header. This header is used to signify whether a particular table was closed properly or not. Sometimes, while using the myisamchk command if you get an error message that means the table has corrupted. Such problems can occur due to various reasons such as power outages, abrupt system shutdown, mysqld process getting killed in between a write operation, etc. You should use in-built workarounds to repair the table. If you are not able to do this, then you should use a third-party MySQL repair software to recover MySQL database.

Consider a scenario wherein you have installed MySQL 5.0 in your system. One day, when you try to run the myisamcheck command to check a database table, it …

With speaker confirmations going out this week, the MySQL track at COLLABORATE 11 – IOUG Forum is filling up with the folks you expect to hear when you go to a MySQL event. Giuseppe Maxia will be playing in the MySQL sandbox, Matt Yonkovit will outline the 7 Deadly Performance Sins, and we’ll have Kaj Arno presenting a look at the MySQL ecosystem.  Oh, and Morgan Tocker. And Alexander Rubin. AND Bill Karwin. It’s like a real MySQL conference – oh wait, it IS a real MySQL conference! Of course, we owe a huge debt of gratitude to our Track Manager, Sheeri Cabral. (She’s presenting too, btw.)

If you haven’t considered COLLABORATE before, think of it as a way to get the best of all educational opportunities – real users and community heroes, combined with the Oracle technical staff who helped to bring you release 5.5.8. Plus, MySQL community members can use offer code …

We talk about HandlerSocket with special guest Patrick Galbraith of Blue Gecko, have some Ear Candy and talk about OSCon and the Strata Conferences

The HandlerSocket announcement blog post from Yoshinori Matsunobu of DeNA: http://yoshinorimatsunobu.blogspot.com/2010/10/using-mysql-as-nosql-stor...

HandlerSocket in Percona's build: http://www.mysqlperformanceblog.com/2010/12/14/percona-server-now-both-s...

PBXT has had it for years: http://pbxt.blogspot.com/2010/12/handlersocket-why-did-out-version-did.h...

sample MySQL settings using HandlerSocket from Patrick:
First you …

In my previous posts I highlighted that one of improvements in Percona Server is support of innodb_log_file_size > 4G. This test was done using Percona Server 5.5.7, but the same performance expected for InnoDB-plugin and MySQL 5.5.

The valid question how long is recovery in this case, so let's test it. I took the same tpcc-mysql 1000W workload with 52GB and 144GB innodb_buffer_pool_size with data located on Virident tachIOn card and killed mysqld after 30 mins of work.

The recovery time after start is:
for 52GB innodb_buffer_pool_size:

PLAIN TEXT CODE:

1. 101220 …

The title says it all. If you don’t know what HandlerSocket is or why you would want to use it you need to reads Yoshinori Matsunobu’s blog post.

Lets get started.

 login as root

Make sure you have these packages installed:

yum install git perl libtool gcc make openssl-devel gcc-c++ perl-DBI perl-DBD-MySQL.x86_64

If you haven’t already, install MariaDB and it’s source do that first and make sure it works. Look here http://askmonty.org/wiki/MariaDB:Download#Packages for the packages.

I’m using CentOS 5.5 x64 so I used:

wget http://ftp.osuosl.org/pub/mariadb/mariadb-5.2.4/kvm-rpm-centos5-amd64/rpms/MariaDB-client-5.2.4-94.el5.x86_64.rpm
 wget http://ftp.osuosl.org/pub/mariadb/mariadb-5.2.4/kvm-rpm-centos5-amd64/rpms/MariaDB-server-5.2.4-94.el5.x86_64.rpm …

A special extended edition of Tech Messages for 2010-12-14 through 2010-12-21:

• Cisco IOS Hints and Tricks: IOS HTTP client sets Host: field to IP address
  Still annoying…
• ACL IP Options Selective Drop – Cisco Systems
  Most networks do not make use of IP options. You can drop packets that contain options with the "ip option drop" global configuration command.
• Which loads faster?
  This tool has it's usefulness. It's especially nice to compare your site to similar sites and see what you can do to improve things.

…

We're publishing a new Strata Gem each day all the way through to December 24. Yesterday's Gem: Turn MySQL into blazing fast NoSQL.

Tomorrow's augmented reality is being built today on mobile devices. The Tasker application for Android is a fun platform for prototyping personal automation and sensing applications. Described modestly as an application which "performs tasks based on contexts," it gives non-programmers access to the sensing and system features of the phone.

Following a simple rule metaphor of taking action upon matched conditions, Tasker can respond …

Within Monty Program Ab we have during this year had a lot of discussions about how to go forward with the MariaDB trademark. It's been clear that everyone wants to have something that is substantially freer than the MySQL trademark to ensure the survival of MariaDB whatever happens to Monty Program Ab.

We wanted to make something that should work well, both for open source and commercial usage (and yes, I know that in some cases these are one and the same), which is not very common with many other trademark policies. My belief is that by having a very liberal trademark policy we will create a bigger ecosystem around MariaDB which will help all of us.

Now we have had a couple of internal drafts (with heavy input from our community advocates) and we have released our first public draft.

Please give us feedback about this either on my …

This is to follow up on my previous post and show the results for MySQL 5.5.8 and Percona Server on the fastest hardware I have in our lab: a Cisco UCS C250 server with 384GB of RAM, powered by a Virident tachIOn 400GB SLC card.

To see different I/O patterns, I used different innodb_buffer_pool_size settings: 13G, 52G, an 144G on a tpcc-mysql workload with 1000W (around 100GB of data). This combination of buffer pool sizes gives us different data/memory ratios (for 13G - an I/O intensive workload, for 52G - half of the data fits into the buffer pool, for 144G - the data all fits into memory). For the cases when the …