Emergency

Monthly Archives: September 2009

Which adaptive should we use?

As you may know, InnoDB has 2 limits for unflushed modified blocks in the buffer pool. The one is from physical size of the buffer pool. And the another one is oldness of the block …

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SystemTap – DTrace for Linux ?

Since DTrace was released for Solaris I am missing it on Linux systems… It can’t be included in Linux by the same reason why ZFS can’t be – it’s licensing issue. Both ZFS and DTrace …

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Queries Active vs Transactions Active

What is wrong here (the part of SHOW INNODB STATUS): ————– ROW OPERATIONS ————– 8 queries inside InnoDB, 9 queries in queue 100 read views open inside InnoDB It is relationship between queries active – …

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Statistics of InnoDB tables and indexes available in xtrabackup

If you ever wondered how big is that or another index in InnoDB … you had to calculate it yourself by multiplying size of row (which I should add is harder in the case of …

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Cache Miss Rate as a function of Cache Size

I saw Mark Callaghan’s post, and his graph showing miss rate as a function of cache size for InnoDB running MySQL. He plots miss rate against cache size and compares it to two simple models: …

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3 ways MySQL uses indexes

I often see people confuse different ways MySQL can use indexing, getting wrong ideas on what query performance they should expect. There are 3 main ways how MySQL can use the indexes for query execution, …

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Sponsoring OpenSQL Camp 2009

We’re supporting the OpenSQL Camp, which will be held in Portland on November 14. One of my objectives for the camp is to make progress on a universal storage engine API, to make it possible …

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What to do with MySQL Full Text Search while migrating to Innodb ?

It is rather typical for systems to start as MyISAM but as system growths to move to Innodb. The reason of the move could be just desire for better data consistency guaranty or being bitten …

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Off to California!

Today’s the day I fly to Los Angeles to teach a private training class, en route to Santa Clara/San Francisco for our public training workshops next week.

Our Montreal practice teach at Station-C went great – it was an opportunity to do a road test and iron out any kinks in the delivery.

What did I learn in the process?

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