… and other non response time critical activities are overloading the system causing user experience to degrade. The first thing you need…. This is true if you have system completely at your disposal. If you however need system to serve other users too you… writing to database. Introduce Throttling Sometimes even single process overloads system too much in this case throttling by having relatively short…
Comment: ext4 vs xfs on SSD
April 24, 2012 By 23 Comments
Vadim, Selecting something as important as an Operating System or major component like a File System on the basis of ONE fairly small… in a way that is “fussy” in the extreme. The systems I put on-line have ZFS and we rely on… comments rather disingenuous. Do you pay license fees for your operating system?
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
… Dictionary cache 512619219 (509995888 + 2623331) File system 294352 (82672 + 211680) Lock system 318875832 (318747272 + 128560) Recovery system 0 (0 + 0) Threads 425080 (406936… total any more as Innodb has moved allocating memory from operation system directly not from addition memory pool (hence 0). Such allocations…
Post: How to diagnose errors in the MySQL error log
March 26, 2012 By 4 Comments
… denied; there is no bug — that error comes from the operating system. Typical causes are things like SELinux or AppArmor interfering. So…
Post: How We Got Here
April 9, 2012 By 6 Comments
… hear from people who use MySQL in production systems and know how to operate it and develop against it. These are the…
Post: Announcement of Percona XtraDB Cluster 5.5.20 GA release
April 3, 2012 By 10 Comments
… deployments RSU, Rolling Schema Update. Schema change does not block operations against table This is an General Availability release. We did…. If you encounter them, please report to our bug tracking system. Links: We provide tar.gz and RPM binaries for RedHat…
Post: Operation Systems do not provide good IO interface for Database Servers
May 11, 2006 By 2 Comments
… is priority. There are process and threads priorities in most operation systems but there is no priority you can set for given… it would be helpful for prioritising transactions inside of database system itself. Normal – As name implies normal IO should be done… any development going on for something like this in modern operation systems. In fact these are not new ideas. I’ve been…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… good idea what hardware and operating system I’m working with. System performance Next I investigate what the system is doing, in terms of performance. There are two key commands for this on most operating systems (there are… of the costs and benefits on the system as a whole. The queries the system runs, and hence the slow query log…
Post: Which Linux distribution for a MySQL database server? A specific point of view.
December 8, 2011 By 37 Comments
… used. All use common Linux kernel – the heart of Linux operating system – which in principle will behave the same way in all… a tiny and unimportant system, but any of these operations may have severe consequences on a large production system. This is why all…, is for example a requirement for commercial support for the operating system. You will have to choose between RedHat or SuSE. Another…
Post: How fast is FLUSH TABLES WITH READ LOCK?
April 24, 2010 By 28 Comments
… relies on the operating system to flush the data blocks to disk when it decides to. As a result, a system that has a lot of MyISAM data might have a lot of dirty blocks in the operating system buffer cache. This can take a long time to flush. During that time, the entire system is still…
