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Showing entries 1 to 6

Displaying posts with tag: config (reset)

MySQL 5.7 default configuration: what’s new? (and what’s not)
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Inspired by Peter Zaitsev’s post for MySQL 5.6, I decided to do a comparison between default configuration of MySQL 5.6 and 5.7. And I gotta tell you, some of the changes I found will have a huge impact on performance so make sure to get yourself familiar with them before you upgrade, even if you’re not otherwise running with a default configuration.

BEGIN

Interestingly, I hit the first roadblock before I could even start. It seems you can no longer extract the same information from the …

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17 Key MySQL Config File Settings (MySQL 5.7 proof)
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When MySQL becomes too slow (or too unstable), temptation usually is to tweak the MySQL configuration file. Indeed, it’s a good place to start. But if you ever looked at the available configuration options, you know things can get messy – MySQL now has over 450 configuration variables for your consideration, that are not classified in any way, and neither of them are included in the stock my.cnf. It’s hard to know where to start!

I’m hoping that this blog post will help you overcome the anxiety of tuning MySQL, whether you’re setting up a new server, or tuning an already running server for better performance.

Don’t do …

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How to find MySQL binary logs, error logs, temporary files?
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Have you ever spent a lot of time trying to locate where MySQL keeps some file? Here is a quick way to find all this information in one place.

The obvious way is through examining database options in my.cnf or looking at the output of SHOW GLOBAL VARIABLES. But not every path may be explicitly set in the configuration, in such case MySQL may assume some default, while other options may be set using relative paths.

A different approach is listing all files that a running database instance keeps open and searching for the required information there. I find that method by far the fastest whenever I need …

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MySQL, OOM Killer, and everything related
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Do the operating systems kill your MySQL instances from time to time? Are some database servers swapping constantly? These are relatively common problems. Why? How to prevent them?

Memory allocation

When a running program needs some additional memory, it can typically allocate it dynamically with malloc() function. It finds an unused continuous block that is at least as large as the requested size, reserves as much as it needs, and returns a pointer to that space. No initialization of the memory contents is performed at the time. When malloc() returns NULL instead of a valid address, it is an information to the …

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Know your my.cnf groups, part II
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Ronald Bradford’s recent warning to be sure to know your my.cnf sections reminded me of a similar issue that I ran into last summer, where putting the “group” option in both the [mysqld_safe] and [mysqld] directives resulted in a mostly silent problem.

I started noticing this in MySQL 5.1 and it affected both the official MySQL binary and the Percona binary. In trying to be conscientious, I had the following set:

[mysqld_safe]
user=mysql




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Sample my.cnf file for InnoDB databases
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Brian Moon suggest that community provided example my.cnf files would be a great thing to have on MySQLforge in this recent post: http://doughboy.wordpress.com/2008/05/06/example-mycnf-files/

I pulled out the "innodb heavy" config sample file and modified it with the standard settings that I typically start with when setting up a new InnoDB master. I've also modified the comments in the file a bit and have added some of my own too. I removed the sample slave configuration parameters (master-host, etc) because you should be using 'CHANGE MASTER TO'.

He suggested …



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Showing entries 1 to 6

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