Emergency

Monthly Archives: June 2010

Purge Thread Spiral of Death

I just wrote a large post on reasons for innodb main tablespace excessive growth and I thought it would make sense to explain briefly of why it is so frequently you have purge not being …

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Reasons for run-away main Innodb Tablespace

So you’re running MySQL With innodb_file_per_table option but your ibdata1 file which holds main (or system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what …

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Table locks in SHOW INNODB STATUS

Quite frequently I see people confused what table locks reported by SHOW INNODB STATUS really mean. Check this out for example:

This output gives us an impression Innodb has taken table lock on test/t1 …

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Making Deletions Fast, by Avoiding Disk Seeks

In my last post, I discussed how fractal tree data structures can be up to two orders of magnitude faster on deletions over B-trees. I focused on the deletions where the row entry is known …

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Performance Optimization and Six Sigma

You might be familiar with Six Sigma business management strategy which is employed by variety of the companies in relationship to managing quality of its product. Six Sigma applies to number of defects – when …

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FlashCache: tpcc workload with FusionIO card as cache

This run is very similar what I had on Intel SSD X25-M card, but now I use FusionIO 80GB SLC card. I chose this card as smallest available card (and therefore cheapest. On Dell.com you …

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PBXT in tpcc-like benchmark

Finally I was able to run PBXT 1.0.11 pre-GA in tpcc-like workload, apparently there was bug with did not allow me to get the result earlier, and I am happy to see that PBXT team …

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Disk seeks are evil, so let’s avoid them, pt. 3 (Deletions)

As mentioned in parts 1 and 2, having many disk seeks are bad (they slow down performance). Fractal tree data structures minimize disk seeks on ad-hoc insertions, whereas B-trees practically guarantee that disk seeks are …

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Security fixes for MySQL 4.0 and 4.1

In Percona Server security fix releases I mentioned patches for MySQL 4.0 and 4.1. I am happy to announce that GoDaddy.com released patches for MySQL 4.0 and MySQL 4.1 under GPL license and you can …

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Color code your performance numbers

When analyzing how good or bad response time is it is not handy to look at the averages, min or max times – something what is easily computed using built in aggregate functions. We most …

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