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Monthly Archives: July 2006

Leaving MySQL, MySQL Consulting

I’m leaving MySQL starting 1st of August. This is surely not news for my collegues and friends who knew this is comming. We’re starting our own company which will provide MySQL Consulting services. We’ll focus …

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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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Returning to InnoDB scalability

I’m again returning to InnoDB scalability and related bug #15815 as it hurts many users and customers using multi-cpu servers. Short intro into problem: On 4-CPU box 1 thread executes full-table scan select query for …

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MySQL Query Cache

MySQL has a great feature called “Query Cache” which is quite helpful for MySQL Performance optimization tasks but there are number of things you need to know. First let me clarify what MySQL Query Cache …

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Extended EXPLAIN

One nice feature added for EXPLAIN statement in MySQL 4.1 is EXTENDED keyword which provides you with some helpful additional information on query optimization. It should be used together with SHOW WARNINGS to get information …

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MySQL EXPLAIN limits and errors.

Running EXPLAIN for problematic queries is very powerful tool for MySQL Performance optimization. If you’ve been using this tool a lot you probably noticed it is not always provide adequate information. Here is list of …

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Stack trace for x86_64 boxes

We are going to release several patches which are not included in official MySQL releases. First one is automatically stack trace for x86_64 systems. Currently MySQL resolves stack in crash only for x86 boxes. You …

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SHOW INNODB STATUS walk through

Many people asked me to publish a walk through SHOW INNODB STATUS output, showing what you can learn from SHOW INNODB STATUS output and how to use this info to improve MySQL Performance. To start …

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eWeek tests OpenSource stacks and .NET

Have you seen recent eWeek benchmarks which test OpenSource stacks and compare them to .NET ? Here is what was compared and here are results. Results make me ask number of questions – why WAMP …

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How much memory Innodb locks really take ?

After playing yesterday a bit with INSERT … SELECT I decided to check is Innodb locks are relly as efficient in terms of low resource usage as they are advertised. Lets start with a bit …

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