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Search Results for: innodb slow update

Improved InnoDB fast index creation

One of the serious limitations in the fast index creation feature introduced in the InnoDB plugin is that it only works when indexes are explicitly created using ALTER TABLE or CREATE INDEX. Peter has already …

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When Does InnoDB Update Table Statistics? (And When It Can Bite)

An InnoDB table statistics is used for JOIN optimizations and helping the MySQL optimizer choose the appropriate index for a query. If a table’s statistics or index cardinality becomes outdated, you might see queries which …

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InnoDB Flushing: Theory and solutions

I mentioned problems with InnoDB flushing in a previous post. Before getting to ideas on a solution, let’s define some terms and take a look into theory. The two most important parameters for InnoDB performance …

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Reasons for run-away main Innodb Tablespace

So you’re running MySQL With innodb_file_per_table option but your ibdata1 file which holds main (or system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what …

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How innodb_open_files affects performance

Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which defines how many files …

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Statistics of InnoDB tables and indexes available in xtrabackup

If you ever wondered how big is that or another index in InnoDB … you had to calculate it yourself by multiplying size of row (which I should add is harder in the case of …

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A few administrative updates

I wanted to write a few administrative updates in one so I didn’t spam everyone’s feed readers too much. Here we go: We’ve had reports of some lost comments.  We reported this via Twitter a …

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Compression for InnoDB backup

Playing with last version of xtrabackup and compress it I noticed that gzip is unacceptable slow for both compression and decompression operations. Actually Peter wrote about it some time ago, but I wanted to review …

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The perils of InnoDB with Debian and startup scripts

Are you running MySQL on Debian or Ubuntu with InnoDB? You might want to disable /etc/mysql/debian-start. When you run /etc/init.d/mysql start it runs this script, which runs mysqlcheck, which can destroy performance. It can happen …

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Some little known facts about Innodb Insert Buffer

Despite being standard Innodb feature forever Insert Buffers remains some kind of mysterious thing for a lot of people, so let me try to explain thing a little bit. Innodb uses insert buffer to “cheat” …

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