Category Archives: yves

The upcoming MySQL UC 2009

The MySQL UC 2009 is coming and it is time for my own little marketing. As Matt already annonced it a few months ago we (Matt and I) are doing a WaffleGrid presentation, Distributed InnoDB caching with Memcached, Tuesday at … Continue reading

Posted in mysql, NDB Cluster, Waffle Grid, yves | 1 Comment

NDB Cluster one step closer to become a DB killer app!

If you have been following the development of the NDB Cluster storage engine lately, you are probably as excited as I am. NDB Cluster is becoming a kind of large database killer app. Look at all the nice features that … Continue reading

Posted in HA, mysql, NDB Cluster, yves | 2 Comments

Improvement in subquery execution with the upcoming MySQL-6.0 branch

Although I know the JOIN syntax very well, IN clauses are often so much easier to read. A few years ago I was developing a custom ERP application on SAPDB/MAXDB (still opensource at the time) and I used extensively IN … Continue reading

Posted in mysql, yves | 3 Comments

Social networking type queries with NDB (part 2)

Recently, I talked about how to optimize social networking type queries for the NDB storage engine using IN clause statements. In clauses are great but they have one fundamental limitation, they work only on one column (Actually, this is not … Continue reading

Posted in HA, mysql, NDB Cluster, yves | 4 Comments

High performance replacement of the MySQL Memory storage engine with NDB

People often wants to use the MySQL memory engine to store web sessions or other similar volatile data. There are good reasons for that, here are the main ones: Data is volatile, it is not the end of the world … Continue reading

Posted in HA, mysql, NDB Cluster, yves | 10 Comments

WaffleGrid ported to the InnoDB plugin 1.0.3

For the interested, I just ported Wafflegrid to the newest version of the InnoDB pluging, v. 1.0.3. Meanwhile, I also corrected a small bug with the CRC_32 code that wrongly cause MySQL to report corrupted blocks after being retrieved from … Continue reading

Posted in mysql, Waffle Grid, yves | 1 Comment

The early end of the MiniWheatFS project for tmpfs with MySQL!!!

I am happy to say that I found a kernel level way to join a ramdisk (actually not a tmpfs strictly speaking) with a normal file system. This cut my motivation for the MiniWheatFS project by 99.999%. I recall that … Continue reading

Posted in linux, mysql, performance, yves | 4 Comments

Social Networking type queries with NDB (part 1)

NDB Cluster is the only integrated sharding framework that I know of (educate me if I am wrong) but it is known to have issues with large joins. These days, large databases that would benefit from a sharding framework are … Continue reading

Posted in HA, mysql, NDB Cluster, performance, yves | 6 Comments

NDB cluster and Max_connections

NDB cluster is a strange beast. Usually, performance wise, it is a good idea to limit the number of threads inside MySQL, that’s why there are parameters like thread_concurrency and innodb_thread_concurrency. MySQL is known to show mutexes contention with a … Continue reading

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InnoDB secondary index file structure

In my previous Post, we took a look at the file structure of the InnoDB primary key index. With the same table structure, but a slightly different dataset: mysql> select * from test_innodb_growth limit 10; +—-+————+——–+ | id | data … Continue reading

Posted in innodb internals, mysql, performance, yves | Comments Off on InnoDB secondary index file structure