Monthly Archives - August 2012

Visualization tools for pt-query-digest tables

When you process MySQL slow query logs using pt-query-digest you can store samples of each query into query_review table and historical values for review trend analysis into query_review_history table. But it could be difficult to easily browse those tables without a good GUI tool.
For the visual browsing of tables created by pt-query-digest you may […]

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268x Query Performance Increase for MongoDB with Fractal Tree Indexes, SAY WHAT?

Last week I wrote about our 10x insertion performance increase with MongoDB. We’ve continued our experimental integration of Fractal Tree® Indexes into MongoDB, adding support for clustered indexes.  A clustered index stores all non-index fields as the “value” portion of the index, as opposed to a standard MongoDB index that stores a pointer to […]

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Month of August in Percona Community Forums

This month was a busy month in Percona Community Forums with a lot of great questions asked and most answered. It is great to see both independent community and Percona employees participating in discussion. Thank you. Here are some things you would learn from following Percona Forums in August:
How to get PAM authentication […]

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Is Replication Slave ever going to catch up? When?!

If you ever had a replication slave that is severely behind, you probably noticed that it’s not catching up with a busy master at a steady pace. Instead, the “Seconds behind master” is going up and down so you can’t really tell whether the replica is catching up or not by looking at just […]

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Differences between READ-COMMITTED and REPEATABLE-READ transaction isolation levels

As an instructor with Percona I’m sometimes asked about the differences between the READ COMMITTED and REPEATABLE READ transaction isolation levels.  There are a few differences between READ-COMMITTED and REPEATABLE-READ, and they are all related to locking.
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Hidden columns of query_review_history table

You can use pt-query-digest to process a MySQL slow query log and store historical values for review trend analysis into query_review_history table. According to its official documentation you can populate many columns in that table but there are other important ones such as ‘user’, ‘host’, ‘db’ which are not included by default. I will […]

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Full Text Search Webinar Questions Followup

I presented a webinar this week to give an overview of several Full Text Search solutions and compare their performance.  Even if you missed the webinar, you can register for it, and you’ll be emailed a link to the recording.
During my webinar, a number of attendees asked some good questions.  Here are their questions and my […]

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10x Insertion Performance Increase for MongoDB with Fractal Tree Indexes

The challenge of handling massive data processing workloads has spawned many new innovations and techniques in the database world, from indexing innovations like our Fractal Tree® technology to a myriad of “NoSQL” solutions (here is our Chief Scientist’s perspective). Among the most popular and widely adopted NoSQL solutions is MongoDB and we became curious […]

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