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Search Results for: check query overload server

MySQL replication primer with pt-table-checksum and pt-table-sync

MySQL replication is a process that allows you to easily maintain multiple copies of MySQL data by having them copied automatically from a master to a slave database. It’s essential to make sure the slave …

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Logging MySQL queries from the client instead of the server

The “slow query log” is the single most valuable way to examine query execution on your MySQL server. Queries are logged with timing information, and in the case of Percona Server, a great deal of …

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Is it query which needs to be optimized ?

Last few days I had a lot of a lot of questions at MySQL Performance Forum as well as from our customers regarding query optimization… which had one thing in common – It is not …

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Introducing email reports for Percona Cloud Tools!

For those PCT users who forget to regularly check query performance, you can now get server query reports delivered to your email daily or weekly. The report contains a digest of the most critical performance …

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Optimizing MySQL for Zabbix

This blog post was inspired by my visit at the annual Zabbix Conference in Riga, Latvia this year, where I gave a couple of talks on MySQL and beyond. It was a two day single-track …

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Innodb transaction history often hides dangerous ‘debt’

In many write-intensive workloads Innodb/XtraDB storage engines you may see hidden and dangerous “debt” being accumulated – unpurged transaction “history” which if not kept in check over time will cause serve performance regression or will …

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Why %util number from iostat is meaningless for MySQL capacity planning

Earlier this month I wrote about vmstat iowait cpu numbers and some of the comments I got were advertising the use of util% as reported by the iostat tool instead. I find this number even more useless for …

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The Math of Automated Failover

There are number of people recently blogging about MySQL automated failover, based on production incident which GitHub disclosed. Here is my take on it. When we look at systems providing high availability we can identify …

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Cache Miss Storm

I worked on the problem recently which showed itself as rather low MySQL load (probably 5% CPU usage and close to zero IO) would spike to have hundreds instances of threads running at the same …

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Goal driven performance optimization

When your goal is to optimize application performance it is very important to understand what goal do you really have. If you do not have a good understanding of the goal your performance optimization effort …

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