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Search Results for: table_cache open files limit

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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Limiting InnoDB Data Dictionary

One of InnoDB’s features is that memory allocated for internal tables definitions is not limited and may grow indefinitely. You may not notice it if you have an usual application with say 100-1000 tables. But …

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MySQL server memory usage troubleshooting tips

There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory usage for MySQL. As a …

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Innotop: A real-time, advanced investigation tool for MySQL

GUI monitoring tools for MySQL are not always suitable for all our needs or situations. Most of them are designed to provide historical views into what happens to our database over time rather then real-time …

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What is the longest part of Innodb Recovery Process ?

In MySQL 4.1 and above the longest part of recovery after crash for Innodb tables could be UNDO stage – it was happening in foreground and was basically unbound – if you have large enough …

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MySQL Crash Recovery

MySQL is known for its stability but as any other application it has bugs so it may crash sometime. Also operation system may be flawed, hardware has problems or simply power can go down which …

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