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Search Results for: pt table sync

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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Syncing MySQL slave table with pt-online-schema-change

I recently encountered a situation in which after running Percona Toolkit’s pt-table-checksum on a customer system, 95% of the table on the MySQL master was different on the MySQL slave. Although this table was not …

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Optimizing PXC Xtrabackup State Snapshot Transfer

State Snapshot Transfer (SST) at a glance PXC uses a protocol called State Snapshot Transfer to provision a node joining an existing cluster with all the data it needs to synchronize.  This is analogous to …

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Optimizing Percona XtraDB Cluster for write hotspots

Some applications have a heavy write workload on a few records – for instance when incrementing a global counter: this is called a write hotspot. Because you cannot update the same row simultaneously from multiple …

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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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Checking table definition consistency with mysqldiff

Data inconsistencies in replication environments are a pretty common. There are lots of posts that explain how to fix those using pt-table-checksum and pt-table-sync. Usually we only care about the data but from time to …

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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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MySQL 5.6 Transportable Tablespaces best practices

In MySQL 5.6 Oracle introduced a Transportable Tablespace feature (copying tablespaces to another server) and Percona Server adopted it for partial backups which means you can now take individual database or table backups and your …

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MySQL’s INNODB_METRICS table: How much is the overhead?

Starting with MySQL 5.6 there is an INNODB_METRICS table available in INFORMATION_SCHEMA which contains some additional information than provided in the SHOW GLOBAL STATUS output – yet might be more lightweight than PERFORMANCE_SCHEMA. Too bad …

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