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Search Results for: mysql deleted tmp files

Log rotate and the (deleted) MySQL log file mystery

Did your logging stop working after you set up logrotate? Then this post might be for you. Some time ago, Peter Boros wrote about Rotating MySQL Slow Logs safely, explaining the steps of a “best …

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How to monitor ALTER TABLE progress in MySQL

While working on a recent support issue as a Percona Support Engineer,  I got one question from a customer asking how to monitor ALTER TABLE progress. Actually, for MySQL 5.5 and prior versions, it’s quite difficult to ALTER the …

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Filling the tmp partition with persistent connections

The use of tmpfs/ramfs as /tmp partition is a common trick to improve the performance of on-disk temporary tables. Servers usually have less RAM than disk space so those kind of partitions are very limited …

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DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL

Suppose you have turned on innodb_file_per_table (which means that each table has its own tablespace), and you have to drop tables in a background every hour or every day. If its once every day then …

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How to Monitor MySQL with Percona’s Nagios Plugins

In this post, I’ll cover the new MySQL monitoring plugins we created for Nagios, and explain their features and intended purpose. I want to add a little context. What problem were we trying to solve …

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Ultimate MySQL variable and status reference list

I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the …

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How to setup a PXC cluster with GTIDs (and have async slaves replicating from it!)

This past week was marked by a series of personal findings related to the use of Global Transaction IDs (GTIDs) on Galera-based clusters such as Percona XtraDB Cluster (PXC). The main one being the fact that …

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OpenStack users shed light on Percona XtraDB Cluster deadlock issues

I was fortunate to attend an Ops discussion about databases at the OpenStack Summit Atlanta this past May as one of the panelists. The discussion was about deadlock issues OpenStack operators see with Percona XtraDB …

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Recovering CREATE TABLE statement from .frm file

So lets say you have .frm file for the table and you need to recover CREATE TABLE statement for this table. In particular when we do Innodb Recovery we often get .frm files and some …

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A quest for the full InnoDB status

When running InnoDB you are able to dig into the engine internals, look at various gauges and counters, see past deadlocks and the list of all open transactions. This is in your reach with one …

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