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Search Results for: mysql ram

How to obtain the MySQL version from an FRM file

I recently helped a customer figure out why a minor version MySQL upgrade was indicating that some tables needed to be rebuilt. The mysql_upgrade program should be run for every upgrade, no matter how big …

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MySQL QA Episode 3: How to use the debugging tool GDB

Welcome to MySQL QA Episode 3: “Debugging: GDB, Backtraces, Frames and Library Dependencies” In this episode you’ll learn how to use debugging tool GDB. The following debugging topics are covered: 1. GDB Introduction 2. Backtrace, Stack …

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Using Cgroups to Limit MySQL and MongoDB memory usage

Quite often, especially for benchmarks, I am trying to limit available memory for a database server (usually for MySQL, but recently for MongoDB also). This is usually needed to test database performance in scenarios with …

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Oracle license revenue and the MySQL ecosystem

Oracle was in the news recently with the story of its license revenue declining as much as 17% in the recent quarter. This is blamed on transitioning to the cloud in some publications, but others, …

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MaxScale: A new tool to solve your MySQL scalability problems

Ever since MySQL replication has existed, people have dreamed of a good solution to automatically split read from write operations, sending the writes to the MySQL master and load balancing the reads over a set …

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Is 80% of RAM how you should tune your innodb_buffer_pool_size?

It seems these days if anyone knows anything about tuning InnoDB, it’s that you MUST tune your innodb_buffer_pool_size to 80% of your physical memory. This is such prolific tuning advice, it seems engrained in many …

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MySQL 5.7 key features

The other day I was discussing new features of MySQL 5.7 with a Percona Support customer. After that conversation, I thought it would be a good idea to compile list of important features of MySQL …

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MySQL indexing 101: a challenging single-table query

We discussed in an earlier post how to design indexes for many types of queries using a single table. Here is a real-world example of the challenges you will face when trying to optimize queries: …

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Keep your MySQL data in sync when using Tungsten Replicator

MySQL replication isn’t perfect and sometimes our data gets out of sync, either by a failure in replication or human intervention. We are all familiar with Percona Toolkit’s pt-table-checksum and pt-table-sync to help us check …

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Optimizer hints in MySQL 5.7.7 – The missed manual

In version MySQL 5.7.7 Oracle presented a new promising feature: optimizer hints. However it did not publish any documentation about the hints. The only note which I found in the user manual about the hints …

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