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Search Results for: set innodb_thread_concurrency

Attempting to Quantify Fragmentation Effects

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We often hear from customers and MySQL experts that fragmentation causes problems such as wasting disk space, increasing backup times, and degrading performance. Typical remedies include periodic “optimize table” or dump and re-load (for example, …

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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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Call for opinions: Do we need MySQL 5.0 with MySQL 5.4 performance

MySQL 5.4 comes with Innodb engine which seems to have much better performance than MySQL 5.0 – this is due to locking and IO patches from Google integrated in this release (which are similar to …

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SSD, XFS, LVM, fsync, write cache, barrier and lost transactions

We finally managed to get Intel X25-E SSD drive into our lab. I attached it to our Dell PowerEdge R900. The story making it running is worth separate mentioning – along with Intel X25-E I …

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iiBench Contest Updates

We re-ran iiBench based on Mark Callaghan’s excellent work. We used standard InnoDB engine in MySQL 5.1 without the Google or Percona patches. Our hardware is similar to Mark’s except we used a 6-disk hardware …

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XtraDB/InnoDB CPU bound benchmarks on 24cores server

One of our customers gave me a chance to run some benchmarks on 24-core (intel cpu based) server, and I could not miss it and ran few CPU-bound tasks there. The goal of benchmarks was …

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MySQL QA Team Benchmarks for MySQL 5.1.30

As you might have seen MySQL QA Team has published their benchmarks for MySQL 5.0.72 and 5.1.30. It is interesting to compare with results I posted previously

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iiBench configuration

A tip of the hat to Mark Callaghan, who suggested I post our my.cnf settings for iiBench. Instead of fiddling around with the configuration file, we adjusted everything on the command line. Here’s the relevant …

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New SpecJAppServer results at MySQL and Sun.

As you likely have seen Sun has posted the new SpecJAppServer Results More information from Tom Daly can be found here These results are quite interesting for me as I worked on some of the …

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Drilling down to the source of the problem

I had an interesting tuning case few days ago. The system serving high traffic using Innodb tables would be stalling every so often causing even very simple queries both reads and writes taking long time …

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