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Displaying posts with tag: optimizations (reset)

Should you disable or enable the MySQL query cache?
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I – What is a query cache?

The MySQL query cache was introduced as part of version 4.0 of MySQL. Its main function is simple: it is a giant hash table that associates bulk SQL queries with a group of results.

It signifies that if you add a space or change a capital letter in your SQL query, it will be different from the query cache point of view.
This simple approach also signifies that with a small modification/writing in a table, all the query cache entries concerning the table in question will be invalidated.
In applications that use the reading in an intensive fashion, without a lot of writing, it seems that enabling the …

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Spreading .ibd files across multiple disks; the optimization that isn’t
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Inspired by Baron's earlier post, here is one I hear quite frequently -

"If you enable innodb_file_per_table, each table is it's own .ibd file.  You can then relocate the heavy hit tables to a different location and create symlinks to the original location."

There are a few things wrong with this advice:

  1. InnoDB does not support these symlinks.  If you run an ALTER TABLE command, what you will find is that a new temporary table is created (in the …
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Innodb monitors show information about innodb internal status - which could be used for performance tuning. Lets break down the output of show engine innodb status and get a look at what is happening and how it can be improved. Just fire the "Show engine innodb status" command and check the Output.mysql> show engine innodb status\G*************************** 1. row ***************************

optimizing mysql guide
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I had written about this but mostly in parts. Here is a step by step guide to optimizing mysql. Following variables should be looked into for optimizing mysql.Memory consumption: Total memory consumption should be less than the available RAM. You should also leave a small amount of memory for the OS. Total memory consumption can be calculated using this formula (for myisam tables):Key_buffer + (

Showing entries 1 to 4

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