Last week both Sheeri and Mark Callaghan pointed my attention to the fact that if they comment on articles on this blog, they end up getting lot of email spam that is sent via OpenLife.cc. Thank you for informing me, I was completely unaware that this was still happening. The problem should now be fixed - you should not get any more spam mail, whether related to your old comments on this site or any new ones I hope you will still make.

When spam bots figured out how to spam Drupal based blogs - including working around the Captcha - I enabled the Drupal Antispam module which uses the Akismet service to check all incoming comments for spam. It has worked very well. On average AntiSpam blocks 40 spam comments a day, and the accuracy is very good (see stats below).

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Ever ran into a situation where you saw “some important variable you really needed to know about=<optimized out>” while debugging? Let’s look at an example:

[Roel@qaserver master-data]$ gdb /percona-server/Percona-Server-5.5.25a-rel27.1-285.Linux.x86_64/bin/mysqld ./core.3200 
[...]
(gdb) bt
[...]
#20 handle_select (thd=0x33acd30, lex=0x33ae900, result=0x7f3e840058d0, setup_tables_done_option=1073741824)
    at /percona-server/5.5/Percona-Server-5.5.25a-rel27.1/sql/sql_select.cc:312
#21 mysql_execute_command (thd=thd@entry=0x33acd30)
    at /percona-server/5.5/Percona-Server-5.5.25a-rel27.1/sql/sql_parse.cc:3138
#22 mysql_parse (thd=thd@entry=0x33acd30, rawbuf=<optimized out>, length=72, parser_state=parser_state@entry=0x7f3ed013f810)
    at /percona-server/5.5/Percona-Server-5.5.25a-rel27.1/sql/sql_parse.cc:5809
#23 dispatch_command (command=COM_QUERY, thd=0x33acd30, packet=<optimized out>, …

The Southern California Linux Expo ( SCALE ) call for papers is now open.

They had a great MySQL day last year and with the help of the MySQL Community they can have another one this year ! The event will be held Februrary 22-24, 2013 at the Hilton Los Angeles Airport Hotel.

I’m sure you’ve heard of Box Anemometer from the Box (MySQL) team, an excellent UI tool based on pt-query-digest. Now the guys from the box team offer us another killer UI tool based on pt-stalk, and I’m sure you will really appreciate to use it !

What is it ?

 
“RainGauge” consists of three parts :

• A set of scripts that collect data about the health of your system and your databases (based on pt-stalk)
• A process that push these data on a centralised place
• A very simple interface to navigate in the collected data

But the collection begins only when specific conditions are triggered, and you choose what these conditions are. Find below the general flowsheet :

…

We released the second beta of MySQL Connector/Python v1.0. You can download v1.0.6 from the MySQL website and the change history can be found in the online manual.

Usually, beta releases do not have big changes, but we had to push some code which did not make the previous one and it really had to go into v1.0. The exceptions raised by Connector/Python are now mapped against the ‘SQLState’ found in the MySQL server errors. This makes it much easier to maintain and clearer which exception can be expected. It is, however, possible to override how errors are …

I’ve blogged before about the way to use numactl to start up mysqld, and thus to try to better spread the memory usage on larger memory servers. This came from an article by Jeremy Cole and is fine. I recently had some issues with mysqld seeming to run out of memory on a box which appeared to have plenty free, so it seemed like a good idea to adapt a minutely collector script I run to include the numa_maps output so that I could see if the failed memory was related to this. So far so good.

Many of the clients that connect to the database servers I manage have a very short connect timeout, typically 2 seconds. In a normal network and under normal conditions this is more than enough to allow for successful operation and if the connect does …

In honor of our fifteenth anniversary, I have assembled a few nostalgic items from our earliest years in business.

On September 7, 1997 I went to the Ottawa U public library to come up with some names for the company Steve Pickard and I wanted to found the next morning. The goal was to choose the company name, register the dot-com, and then go incorporate it. I really felt that I lucked out when I discovered the word Pythian, which means “about the Pythia“. The Pythia was the Oracle of Delphi in ancient Greece. (Remember that we launched as an Oracle ecosystem services company, and our other practices came afterwards with MySQL launching in 2002 and SQL Server launching in 2005).

I was also delighted that the Pythian Games were also hosted by the Pythia, and those were the most important …

Ever since the slow query log gained the ability to set sub-second threshold times, it's become the most important source of query performance data you have.  Sure, you can log query latency and throughput from your application, but your application can't tell you how many rows that query examined internally, how much time the query spent waiting for locks or if the query wrote a temp table to disk during its execution.

Improvements in PERFORMANCE_SCHEMA in 5.6 are starting to expose the level of performance data needed to track query performance in detail without the slow query log, but until everyone upgrades, and adjusts their monitoring, the slow query log will still be the premier place to get data.

So on that note, here's …

I’ve just released innotop version 1.9.0. This version fixes a lot of bugs, makes the tool work better when monitoring dozens of MySQL servers, and adds two new modes: a Health Dashboard and an InnoDB Blockers/Blocked mode.

Further Reading:

• A new dashboard for innotop
• innotop version 1.8.0 released
• Version 0.1.106 of innotop MySQL/InnoDB monitor released
• Getting ready for a new …

Well, it is getting closer and closer to the end of the 3rd quarter of 2012, and so we are starting to hunker down and make sure our goals get met. One of those goals is to start running regular checksums on our databases, so that when doing a switchover (a manual “failover” for maintenance purposes) or when taking backups we can ensure we have maintained the same level of data integrity that the master has. And, of course, monitor the output of those checksums with Nagios. So this week has seen a lot of fiddling with pt-table-checksum to get the appropriate values….without further ado, here’s the list of what the database team did this week:

• Found out the hard way that slow_query_log=ON is silently ignored by MySQL, and that the syntax to turn on the slow query logs is …