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Search Results for: query progress

New TokuDB 2.2.0 feature: more query progress information

Last spring, we added a feature that allows the user to see the progress of writes in a statement. Vadim liked it. In 2.2.0, in “show processlist”, we add progress information on reads. Here is …


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 …


[ERROR] mysqld: Sort aborted: Server shutdown in progress

Recently, one of our support customers faced this: “[ERROR] mysqld: Sort aborted: Server shutdown in progress.” At first it would appear this occurred because of a mysql restart (i.e. the MySQL server restarted and the …


MySQL 6.0 Subquery optimizations are published.

Sergey Petrunia brought to my attention the work Optimizer Team has done in MySQL 6.0 related to SubQuery Optimization. I am excited to see this information published honestly outlining the things which are fixed now …


Getting to know TokuDB for MySQL

During last April’s Percona Live MySQL Conference and Expo, TokuDB celebrated it’s first full-year as an open source storage engine. I still remember reading the official announcement and the expectations it created one year ago. The …


Never Settle for a “B”

OldSQL DBs based on B-trees have some well-known problems and workarounds. TokuDB is a NewSQL storage engines based on Fractal Tree indexing, so the natural question is how InnoDB practice translates into TokuDB. This post …


How small changes impact complex systems – MySQL example

If you’ve been studying complex systems you know what minor changes might cause consequences of much greater proportions, sometimes causing some effects that are not easily explained at first. I recently ran across a great …


Schema changes in MySQL for OpenStack Trove users

People using OpenStack Trove instances can hit a common issue in the MySQL world: how to perform schema change operations while minimizing the impact on the database server? Let’s explore the options that can allow …


Sys Schema for MySQL 5.6 and MySQL 5.7

Performance Schema (P_S) has been available since MySQL 5.5, more than 4 years ago. It is still difficult to see production servers with P_S enabled, even with MySQL 5.6 where the feature is enabled by …


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 …