Monty gave us a quick overview of next generation of MyISAM. It is set to include:
No details of time frame were given for delivery, however development is well underway.
The news is out that Java is free. I suspect that 20-30 bloggers are going to steal that title (Free as in Java) so I wanted to try to get my blog post out first. Tim Bray has the news and apparently SUN is going to have an announcement on this tomorrow morning.
In a former life I was a major contributor to java.apache.org which was the precursor to Jakarta and participated in Tomcat and Ant when they were released. I was also the lead developer and project founder of Jetspeed and invented the Portlet API *which have now essentially evolved into widgets). I've also contributed to GNU Classpath and GCJ. Long story short I have a vested interest in seeing Java …
[Read more]The first MySQL Camp is over. A whopping 223 registered attendees, most of whom were overwhelmingly active participants. Plenty of valuable feedback. Constant attention by Ken Jacobs (who assured the audience that “Oracle would never do anything to harm MySQL“), VP of Oracle. Superb Google hosting, facilities, food. Lots of beer by Proven Scaling. Fantastic sessions. What more could one hope for?
Thank you, Google! Thank you, Jay! Thank you, MySQL campers!
I’ve talked about disk space allocation previously, mainly revolving around XFS (namely because it’s what I use, a sensible choice for large file systems and large files and has a nice suite of tools for digging into what’s going on).Most people write software that just calls write(2) (or libc things like fwrite or fprintf) to do file IO - including space allocation. Probably 99% of file io is fine to do like this and the allocators for your file system get it mostly right (some more right than others). Remember, disk seeks are really really expensive so the less you have to do, the better (i.e. fragmentation==bad).
I recently (finally) wrote my patch to use the xfsctl to get
better allocation for NDB disk data files (datafiles and
undofiles).
patch at:
http://lists.mysql.com/commits/15088
What the?
Well this is the inheritance diagram of the Item Class in the MySQL 5.1 Source tree, nicely documented using the Doxygen tool as mentioned by Jay in his presentation at MySQL Camp.
Jay started the Community Doxygen Project on the Forge to improve the level of commenting enabling a better platform for the community to contribute MySQL server code changes.
At this early stage David Shrewsbury is working on fine tuning initial documentation examples for QA and review. You can check out the Status Page of automated commenting conversion.
You can see the present documentation of MySQL 5.1 source …
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This is the first tutorial of a series dedicated to testing
techniques.
Soon all this material will find a home in a more appropriate
place. In the meantime, enjoy the lecture!
While testing large tables, it is useful to test if two tables
have the same contents. For example, if you want to compare
performance between two tables using different storage engines,
or tables created on different filesystems, you must be sure that
both tables have the same content. Having loaded both from the
same source is not a guarantee that the contents are the same: a
mistake or different SQL modes used during the load may result in
substantial differences.
General conceptsThen, you need to compare two, possibly very
large tables. There are several methods available. One is to run
a query with a LEFT OUTER JOIN. However, this method is likely to
take very long or even exhaust your system resources if your
tables are really large.
…
My new Google family since I’ve now moved to the US. Ronald, James, Michael, Shona and Kynan (front). James has literally been here in the US only a few days more then me, and he has an amazing Day 1 story.
Apparently there are a reasonable number of Australians now working for Google. Another interesting fact is the male/female ratio is 6:1 which is extremely high in comparison to the IT industry and IT related university studies.
So, mid morning especially after having a heavy and late night
drinking with new friends in Palo Alto I was seeking at Day #3 of
the MySQL
Camp a high-caffeine pick me up drink. Yesterday I had a
Bawls, and after enjoying it I was a little
concerned that when I returned to New York I would not be able to
buy it. You can get it at Think Geek but that’s more complicated then a
local supermarket.
So after getting a Googler to get me to the cafe fridge we find out that there weren’t any there. No problem, lets just go this way I’m told. So we start a quick tour of the larger cafe area and another set of fridges but no Bawls, we keep walking, no more again. At this time the recommendation is I should try a Rockstar, but so …
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Today I noticed one of server used for web request profiling
stats logging is taking about 2GB per day for logs, which are
written in MyISAM table without indexes. So I thought it is great
to try how much archive storage engine could help me in this
case.
Original Table:
PLAIN TEXT SQL:
As you probably know PHP "mysql" extension supported persistent connections but they were disabled in new "mysqli" extension, which is probably one of the reasons some people delay migration to this extension.
The reason behind using persistent connections is of course
reducing number of connects which are rather expensive, even
though they are much faster with MySQL than with most other
databases.
Not only connects are expensive but you also may run into the trouble establishing number of connections you need. The problem is there can be only so many connections active between Host "Apache" and Host "MySQL": Port 3306 as connection in TCP/IP protocol is identified by pair of IP addresses and pair of ports (local port and remote port). Yes if you're establishing thousands of connections per second you normally do not keep it open for long time, but Operation System does. According to TCP/IP protocol Ports can't be recycled …
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