1. Backup script

#!/bin/sh
# Fri Jun 27 10:44:49 2014
# done by dragkh
# usage: 
# cat /etc/cron.d/backupmysql 
# 0  3  *  *  *       root    /root/bin/clean.backup.hyperion.mysql.mydumper.daily.sh >>  /var/log/clean.backup.${HOSTNAME}.mysql.mydumper.daily.log 2>&1
# 35  3  *  *  *       root    /root/bin/backup.hyperion.mysql.mydumper.daily.sh >> /var/log/backup.${HOSTNAME}.mysql.mydumper.daily.log 2>&1

ROOT_BACKUP_DIR="/home/mydumper"

seik_date () {
if [ -z $1 ]
then
# cdate=`date +%Y-%m-%d\ %H:%M:%S\ %Z`; export cdate; echo $cdate
cdate=`date -R`; export cdate; echo $cdate
else

if [ -z ${2} ]
then
cdate=`date +%Y-%m-%d.%H.%M.%S`; export cdate; echo $cdate
else
cdate=`date "+%Y-%m-%d %H:%M:%S"`; export cdate; echo $cdate
fi

fi
}


function check_dir {
 test ! -d "${1}" && mkdir -p "${1}"
}


function set_cpu_threads {
    # set the threads one less than the existing 
    threads=$(cat /proc/cpuinfo  |  grep processor | tail -1 | …

In this post I would like to review how my dumper for MySQL works from the point of view of locks. Since 0.6 serie we have different options, so I will try to explain how they work

As you may know mydumper is multithreaded and this adds a lot of complexity compared with other logical backup tools as it also needs to coordinate all threads with the same snapshot to be consistent. So let review how mydumper does this with the default settings.

By default mydumper uses 4 threads to dump data and 1 main thread

Main Thread

• FLUSH TABLES WITH READ LOCK

Dump Thread X

• START TRANSACTION WITH CONSISTENT SNAPSHOT;
• dump non-InnoDB tables

Main Thread

• UNLOCK TABLES

Dump Thread X

• dump InnoDB tables

As you can see in this case we need FTWRL for two things, coordinate transaction’s snapshots …

TL;DR version: The backup locks feature introduced in Percona Server 5.6.16-64.0 is a lightweight alternative to FLUSH TABLES WITH READ LOCK and can be used to take both physical and logical backups with less downtime on busy servers. To employ the feature with mysqldump, use mysqldump --lock-for-backup --single-transaction. The next release of Percona XtraBackup will also be using backup locks automatically if the target server supports the feature.

Now on to the gory details, but let’s start with some history.

In the beginning…

In the beginning there was FLUSH TABLES, and users messed with their MyISAM tables under a live server and were not ashamed. Users could do nice things like:

mysql> FLUSH TABLES;
# execute myisamchk, myisampack, backup / restore some tables, etc.

And users were happy until someone realized that tables must be …

One of the tasks within Percona Remote DBA is to ensure we have reliable backups with minimal impact. To accomplish this, one of the tools our team uses is called mydumper. We use mydumper for logical backups because of several nice features. Some of them are:

• multithreaded, producing very fast backups compared to mysqldump
• almost no locking, if not using non innodb tables
• built-in compression
• separate files for each table, making it easy to restore single tables or schema, and the possibility to hardlink files reducing the space needed to keep history of backups. Also this feature give you the possibility to restore with more than one thread.

The mydumper project was started at the beginning of 2009 by …

MySQL has exceptional track of record by introducing minor fixes that cause major breakages. Though usually I could blame naiveté of engineers, who did not really ever have to deal with production implications, but lately I can start sensing various business implications against open-source offerings.

As an original author of mydumper I really cannot get out of my mind that 5.5 and 5.6 metadata locking changes are there to screw with anyone who is building a backup solution using stable snapshot views of MySQL (for example, mysqldump –single-transaction, the golden standard of backing things up in MySQL world).

As seen in a bug #71017 (palindrome!) filed by my esteemed colleague Eric, newly introduced behaviors …

First of all, I wish you a happy new year.
Many things happened last year, it was really exciting to be involved in the MySQL ecosystem.
I hope this enthusiasm will be increased this year, up to you !

To start the year, I propose the MySQL[plus] Awards 2011
It will only take 5 minutes to fill out these polls.
Answer with your heart first and then with your experience with some of these tools or services.

Polls will be closed January 31, so, vote now !
For “other” answers, please,  let me a comment with details.

Don’t hesitate to submit proposal for tools or services in the comments.
And, please, share these polls !

Note: There is a poll embedded within this post, …

After much feedback from the community who have been using mydumper I have created the first bugfix release of the 0.5 series of mydumper.  Changes in this release are as follows:

• 
  
• Fix MySQL 5.0 compile issue
  
• Make the metadata file visible (after muliple requests)
  
• Add --no-lock option to mydumper
  
• First --daemon snapshot is now at execution instead of the first timed interval
  
• Fix CentOS 5.x compile issue (also affected Mac OSX)
  
• Fix libmysqlclient search bug
  
• Add cppcheck target
  
• Fix errors flaged by cppcheck
  
• Add option to turn off docs build
  
• Add status output at end of CMake
  

To obtain this release you can download it from …

After much feedback from the community who have been using mydumper I have created the first bugfix release of the 0.5 series of mydumper.  Changes in this release are as follows:

• Fix MySQL 5.0 compile issue
• Make the metadata file visible (after muliple requests)
• Add –no-lock option to mydumper
• First –daemon snapshot is now at execution instead of the first timed interval
• Fix CentOS 5.x compile issue (also affected Mac OSX)
• Fix libmysqlclient search bug
• Add cppcheck target
• Fix errors flaged by cppcheck
• Add option to turn off docs build
• Add status output at end of CMake

To obtain this release you can download it from Launchpad.

Many thanks to everyone who has been …

It has happened to the best of us.  Our MySQL servers are running nicely when the tea-lady in the data centre trips over a wire, knocks a cup hot of java down the UPS batteries and fries every server in the data centre.  OK, so that doesn't happen very often, but there have been cases where data centre failures have physically damaged servers.

So, if this happens with your MySQL server, what do you do?  You can setup new servers in a new data centre and hope you have an up-to-date backup.  But unless you had remote slaves these backups probably won't be as current as they could be.  When you get to the point where you have many servers keeping slaves for every one just for backups can be difficult to maintain.  Many DBAs have different backup strategies to cover this potential problem.

This is where the new mydumper 0.5.0 comes in. …

It has happened to the best of us.  Our MySQL servers are running nicely when the tea-lady in the data centre trips over a wire, knocks a cup hot of java down the UPS batteries and fries every server in the data centre.  OK, so that doesn’t happen very often, but there have been cases where data centre failures have physically damaged servers.

So, if this happens with your MySQL server, what do you do?  You can setup new servers in a new data centre and hope you have an up-to-date backup.  But unless you had remote slaves these backups probably won’t be as current as they could be.  When you get to the point where you have many servers keeping slaves for every one just for backups can be difficult to maintain.  Many DBAs have different backup strategies to cover this potential problem.

This is where the new mydumper 0.5.0 comes in.  It has …