Why This Post
While testing Yoshinori Matsunobo's MHA agent I found that although the wiki has a very complete documentation, it was missing a some details. This article intends to close that gap and bring up some issues to keep in mind when you do your own installation. At the end of the article I added a Conclusions section, if you're not interested in the implementation details, but to read my take on the project, feel free to jump straight to the end from here.

My Test Case
Most of our production environments can be simplified to match the MHA's agent most simple use case: 1 master w/ 2 or more slaves and at least one more slave in an additional tier:

Master A --> …

I am writing this on my blog because I want to take the Percona hat off (partially) and wear my community hat a bit. My loyalty was to the MySQL community long before I was involved with Percona. There are now three Percona Live events for which we have signed venue contracts and begun plans: London in October, Washington DC in January, and Santa Clara in April. I have insider knowledge of what’s going on with planning all three events, and I’m proud and happy that I have a community-member seat at the table.

More details to come soon

Percona is glad to announce the release of Percona Server 5.1.58-12.9 on August 12, 2011 (Downloads are available here and from the Percona Software Repositories).

Based on MySQL 5.1.58, including all the bug fixes in it, Percona Server 5.1.58-12.9 is now the current stable release in the 5.1 series. All of Percona’s software is open-source and free, all the details of the release can be found in the 5.1.58-12.9 milestone at Launchpad.

Highlights Performance Improvements

• fsync() has been replaced …

Percona is glad to announce the release of Percona Server 5.5.14-20.5 on August 12, 2011 (Downloads are available here and from the Percona Software Repositories).

Based on MySQL 5.5.14, including all the bug fixes in it, Percona Server 5.5.14-20.5 is now the current stable release in the 5.5 series. All of Percona’s software is open-source and free, all the details of the release can be found in the 5.5.14-20.5 milestone at Launchpad.

Improvements

Performance Improvements

• fsync() has been replaced …

The 2011 DevProConnections CommunityChoice Awards has two categories that include nominations for MySQL Workbench !
You can support MySQL Workbench with your vote. The two categories that include Workbench are, “Component Set” (page 1 # 7) and “IDE” (page 2 #14).
The survey is available here and information about workbench is always available here: http://www.mysql.com/products/workbench/

ZFS is a new kind of 128-bit file system that provides simple administration, transactional semantics, end-to-end data integrity, and immense scalability. ZFS is not an incremental improvement to existing technology; it is a fundamentally new approach to data management. ZFS was first introduced in Solaris in 2004 and it is a default filesystem in OpenSolaris, but Linux ports are underway, Apple is shipping it in OS X 10.5 Leopard with limited zfs capability ( Apple shutdown this project afterward due to some known reason), and it will be included in FreeBSD 7.
ZFS Features:

• Pooled Storage Model
• Always consistent on disk
• Protection from data corruption
• Live data scrubbing
…

When EXPLAIN shows that a table is accessed using the [eq_]ref access type, we're used to look at the ref column to see where MySQL gets the value to look up from. Usually, we see either "const" if the value is provided as a constant in the query or a column name if the value is read from a column in an already read table:

EXPLAIN 

SELECT acc_rec.cust_id, acc_rec.amount, acc_rec.invoicenumber

FROM accounts_receivable as acc_rec

WHERE acc_rec.cust_id=1;

+----+-------------+---------+------+---------+-------+

| id | select_type | table   | type | key     | ref   |

+----+-------------+---------+------+---------+-------+

| 1  | SIMPLE      | acc_rec | ref  | cust_id | const |

+----+-------------+---------+------+---------+-------+


EXPLAIN 

SELECT acc_rec.cust_id, acc_rec.amount, acc_rec.invoicenumber,

       customers.firstname, customers.lastname, customers.phone

FROM …

This script is used to check the user security in MySQL server. Prerequisites: Perl modules : DBI, Getopt::Long and Text::Table Script will check following details from mysql grant tables. # Looks for anonymous user accounts # Looks for accounts accessible from any host # Looks for accounts with empty password # Looks for accounts with [...]

Register yourself here

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