table_cache negative scalability
Couple of months ago there was a post by FreshBooks on getting great performance improvements by lowering table_cache variable. So I decided to investigate what is really happening here.The “common...
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How innodb_open_files affects performance
Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which...
View ArticleHow many partitions can you have ?
I had an interesting case recently. The customer dealing with large MySQL data warehouse had the table which was had data merged into it with INSERT ON DUPLICATE KEY UPDATE statements. The performance...
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Tuning InnoDB Concurrency Tickets
InnoDB has an oft-unused parameter innodb_concurrency_tickets that seems widely misunderstood. From the docs: “The number of threads that can enter InnoDB concurrently is determined by the...
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MySQL 5.5.8 and Percona Server: being adaptive
As we can see, MySQL 5.5.8 comes with great improvements and scalability fixes. Adding up all the new features, you have a great release. However, there is one area I want to touch on in this post....
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Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
Part of the InnoDB duties, being an MVCC-implementing storage engine, is to get rid of–purge–the old versions of the records as they become obsolete. In MySQL 5.1 this is done by the master InnoDB...
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Aligning IO on a hard disk RAID – the Benchmarks
In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we get from a proper IO alignment on a...
View ArticleImplications of Metadata Locking Changes in MySQL 5.5
While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the...
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Innotop: A real-time, advanced investigation tool for MySQL
GUI monitoring tools for MySQL are not always suitable for all our needs or situations. Most of them are designed to provide historical views into what happens to our database over time rather then...
View ArticleMySQL server memory usage troubleshooting tips
There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory...
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Looking deeper into InnoDB’s problem with many row versions
A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of...
View ArticleClik here to view.
How innodb_open_files affects performance
Recently I looked at table_cache sizing which showed larger table cache does not always provides the best performance. So I decided to look at yet another similar variable – innodb_open_files which...
View ArticleHow many partitions can you have ?
I had an interesting case recently. The customer dealing with large MySQL data warehouse had the table which was had data merged into it with INSERT ON DUPLICATE KEY UPDATE statements. The performance...
View ArticleClik here to view.
Tuning InnoDB Concurrency Tickets
InnoDB has an oft-unused parameter innodb_concurrency_tickets that seems widely misunderstood. From the docs: “The number of threads that can enter InnoDB concurrently is determined by the...
View ArticleClik here to view.
MySQL 5.5.8 and Percona Server: being adaptive
As we can see, MySQL 5.5.8 comes with great improvements and scalability fixes. Adding up all the new features, you have a great release. However, there is one area I want to touch on in this post....
View ArticleImplications of Metadata Locking Changes in MySQL 5.5
While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the...
View ArticleClik here to view.
Innotop: A real-time, advanced investigation tool for MySQL
GUI monitoring tools for MySQL are not always suitable for all our needs or situations. Most of them are designed to provide historical views into what happens to our database over time rather then...
View ArticleMySQL server memory usage troubleshooting tips
There are many blog posts already written on topics related to “MySQL server memory usage,” but nevertheless there are some who still get confused when troubleshooting issues associated with memory...
View ArticleClik here to view.
Looking deeper into InnoDB’s problem with many row versions
A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of...
View Article