Xaprb » MySQL http://www.xaprb.com/blog Stay curious! Thu, 09 Feb 2012 03:58:56 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 Free webinar on preventing MySQL downtime http://www.xaprb.com/blog/2011/10/13/free-webinar-on-preventing-mysql-downtime/ http://www.xaprb.com/blog/2011/10/13/free-webinar-on-preventing-mysql-downtime/#comments Thu, 13 Oct 2011 16:56:14 +0000 Xaprb http://www.xaprb.com/blog/?p=2510 Further Reading:]]> I’ll be presenting a free one-hour webinar on preventing downtime in production MySQL servers, in conjunction with the ODTUG. It is scheduled on Thursday, November 10, 2011 3:00 PM – 4:00 PM EST, and you can register for free.

Here’s an abstract of what you’ll learn:

Everyone wants to prevent database downtime by being proactive, but how effective are the common measures such as inspecting logs and analyzing SQL? To be truly proactive, one must prevent problems, which requires studying and understanding the reasons for downtime. We have analyzed a selection of emergency issues that we have solved, to better understand what types of problems really occur in production environments. The results are somewhat surprising, and will be detailed in this talk. Most incidents we found were not MySQL-specific and will be familiar to Oracle DBAs as well as MySQL DBAs. This presentation will be valuable for the new or seasoned DBA, as well as to operational managers/directors and CTOs responsible for business critical implementations.

Please register today and I look forward to joining you.

Further Reading:

]]> http://www.xaprb.com/blog/2011/10/13/free-webinar-on-preventing-mysql-downtime/feed/ 1 More on measuring IO latency http://www.xaprb.com/blog/2011/05/24/more-on-measuring-io-latency/ http://www.xaprb.com/blog/2011/05/24/more-on-measuring-io-latency/#comments Tue, 24 May 2011 22:17:10 +0000 Xaprb http://www.xaprb.com/blog/?p=2337 Further Reading:]]> To follow on to my earlier links to Brendan Gregg’s blog posts on measuring I/O latency, there is a third one discussing DTrace, and then a very detailed response from Mark Leith showing how to do it with the PERFORMANCE_SCHEMA in MySQL 5.5.

Further Reading:

]]> http://www.xaprb.com/blog/2011/05/24/more-on-measuring-io-latency/feed/ 0 No Hotsos? Go to the MySQL Conference instead. http://www.xaprb.com/blog/2011/03/08/no-hotsos-go-to-the-mysql-conference-instead/ http://www.xaprb.com/blog/2011/03/08/no-hotsos-go-to-the-mysql-conference-instead/#comments Tue, 08 Mar 2011 18:38:18 +0000 Xaprb http://www.xaprb.com/blog/?p=2229 Further Reading:]]> I wish I could be at the Hotsos Symposium. I would keep my mouth very tightly closed and my ears wide open, and try to learn from people who are completely out of my league about performance analysis topics I won’t grok for another decade (if I’m lucky). But I just can’t cram in that much travel.

If you’re like me, why don’t you go to the O’Reilly MySQL Conference instead? I’ll be trying my feeble best to bring some of the Oracle performance scientist’s mentality to this event, with presentations such as my Forecasting MySQL Performance and Scalability session. And a lot of smart people will be there from many database communities. Percona has a 20% discount, too — not a bad enticement.

Further Reading:

]]> http://www.xaprb.com/blog/2011/03/08/no-hotsos-go-to-the-mysql-conference-instead/feed/ 0 New Aspersa I/O analysis tool, diskstats http://www.xaprb.com/blog/2011/02/05/new-aspersa-io-analysis-tool-diskstats/ http://www.xaprb.com/blog/2011/02/05/new-aspersa-io-analysis-tool-diskstats/#comments Sun, 06 Feb 2011 03:21:51 +0000 Xaprb http://www.xaprb.com/blog/?p=2194 Further Reading:]]> I’ve just committed some changes to diskstats, an I/O analysis tool in Aspersa that’s actually been in the Subversion repository for a long time, but in a barely usable fashion and with no documentation. Now it’s usable and documented.

It is basically a reimplementation of iostat in awk. Why on earth would I reinvent that wheel? Because I spend a lot of time gathering and analyzing raw data from /proc/diskstats, which is vital to really understanding what the storage subsystem is doing. The iostat tool hides important details. Seeing that detail has immediately solved many a disk performance problem and proven SAN vendors wrong, for instance. (I used to do this the old-fashioned way.) Disk performance, of course, is one of the most important things to analyze in a database server that’s struggling.

Also, iostat isn’t interactive, and I wanted an interactive, menu-driven tool to quickly slice and dice the data and drill down into what is happening with I/O. The data it accepts is in the same format as that stored by the stalk and collect tools, which is my default post-mortem toolset. And finally — and I know this might be hard to believe — I’ve been asked to fix problems many times on systems that don’t have iostat and I am not allowed to install it.

And wouldn’t you know it, as I wrote the user’s manual I found a bug, after all my ranting about how other tools show I/O stats wrong. I don’t have time to diagnose or fix the bug right now, so maybe someone else can contribute that. There is a test suite (remind me to explain sometime how I make Bash scripts highly testable) so if we find the problem and fix it, it’ll stay fixed. Contribute your fix to the bug report :-)

Further Reading:

]]> http://www.xaprb.com/blog/2011/02/05/new-aspersa-io-analysis-tool-diskstats/feed/ 4 MySQL and PostgreSQL cross-links http://www.xaprb.com/blog/2011/02/03/mysql-and-postgresql-cross-links/ http://www.xaprb.com/blog/2011/02/03/mysql-and-postgresql-cross-links/#comments Thu, 03 Feb 2011 17:01:07 +0000 Xaprb http://www.xaprb.com/blog/?p=2190 Further Reading:]]> A couple of extremely informative recent blog posts have gone to either Planet MySQL or Planet PostgreSQL, but not both, and I think everyone on both aggregators who cares about database internals should be interested in them. Here they are:

Happy cross-pollination.

Further Reading:

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