… because it is important to understand. What is …It is my belief that the lack of understanding of this system, or even that it…it needs replication to pause and when it is ready for… Despite its name, this setting really does no… to 0.5, meaning the queue had … depends only the size of the transactions,…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…what kind of I/O system is under the box in general. dmesg is useful for several reasons. For one thing, it…meaning of the output, so it‘s clear what I’m showing them. Then, I go through it…
Post: Reasons for run-away main Innodb Tablespace
June 10, 2010 By 2 Comments
…system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what you can do about it… means undo space can just grow until it consumes all free space (or specified max size for …, which works a bit faster as it does not need to compete with other…
Post: System size and Performance Optimization
February 27, 2007 By 2 Comments
… systems running other databases or no database at all as well. So how does System size come in play here ? Well it is system size and scale what… of course does not mean all simple architectures scale badly – for many tasks simple architectures can be good enough, but it should be right…
Post: Using LoadAvg for Performance Optimization
December 4, 2006 By 5 Comments
… in the value than old one. What does Load Average corresponds to ? At least on Linux it is number of processes which are… thing is to understand LoadAvg values are relative to your system size. If you have single CPU and 1 disk loadavg of… of other effects coming in play but good enough for sake of explanation. What does it mean from LoadAvg standpoint ? You need to understand where…
Post: MySQL Sizing questions
June 23, 2006 By 4 Comments
…it hard even to give sizing recomendations even if application is defined. For example if you would ask me what hardware you need for…it means $26 billions per year. This is more than Amazon.com does…
Post: How multiple disks can benefit for single client workload ?
April 26, 2008 By 4 Comments
… for it to complete before continuing. Though in decent systems…means single outstanding disk IO request at all times. So natively it can benefit from multiple hard drives this way. But what…account for it. If we take 15K RPM Hard Drive it does… various seriolization, stripe sizes, cache policies…
Post: Is disk Everything for MySQL Performance ?
April 25, 2008 By 7 Comments
…it is not always the case. There are whole classes of systems where Disk performance is not that important – consider for example systems…does it mean if you have array with 50 hard drives it…
Post: fadvise - may be not what you expect
April 2, 2010 By 7 Comments
…system call to avoid caching in OS cache. We recently made patch for…does not really do what I expected (I used this call as it is often suggested for this purpose). In fact it does not prevent caching, it…; … } which means that Linux kernel does…it works, it only uses OS cache with one block size…
Post: Percona Launches New Support Option for MySQL
October 5, 2010 By 9 Comments
…what does this new service really mean for you, in practical terms? This is actually important — it will open up a range of new choices for…it sometimes makes it hard to give good response time when needed. Our new system…
