A couple of new webinar recordings are available from our web site:
Like our live webinars, the recordings are of course free of charge. Enjoy!
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I very much like the fact that MySQL allows you to embed comments into SQL statements. These comments are extremely convenient, because they are written into MySQL log files as part of the query. This includes the general log, the binary log and the slow query log. Maatkit includes tools which interact with these logs, including mk-query-digest. This tool, in particular, has a very nice option called --embedded-attributes which can process data embedded in query comments.
The support for embedded attributes makes some cool tricks possible. Peter and I co-presented a talk at this past MySQL Conference and Expo. In this talk I presented my Instrumentation-for-PHP class as a demonstration …
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InnoDB uses fuzzy checkpoints. If you search, you can
find some details on this. I don't think the
behavior of it is widely understood. There are few details in
SHOW INNODB STATUS unless you use the Facebook patch and it is
easy to miss this problem.
InnoDB uses a background thread to request and perform writes for
dirty pages when there are too many dirty pages. This is done by
background threads to avoid delaying foreground threads and to
use IO capacity when a server is otherwise idle. I draw a
distinction between request and perform.
Background IO threads perform the IO operation in Linux by
calling write or pwrite. By request …
It seems like everyone in the MySQL community has been chiming in on the so-called “open core” versus Open Source debate. It seems like at least one potential opinion has been unsaid so far, and it’s the one I share: It doesn’t matter if you’re closed source, “open core”, or Open Source, as long as you are completely honest with your customers and/or your users about which of those you are, and that you communicate any changes, particularly in a more closed direction.
I think this is the problem that MySQL (regardless of owners) have suffered in the past — they faced pressure to make money (which is fine), and they decided to used closed source approaches to do so (which is fine), and they picked some features, which they’d promised their users for a long time, to do it with (which is fine, although arguably not that nice), and they failed to communicate it well to either users or customers (which is tragic). The end result …
[Read more]Chances are, if you write Java applications using MySQL’s Connector/J driver, you’ve run across the autoReconnect property. I remember that when I first found it, it seemed I had found the grail itself. “No more nasty connection closed error messages,” I thought. Except … it doesn’t really work that way, does it? I’ve seen this question asked many times in many different contexts: “Why doesn’t Connector/J just reconnect to MySQL and re-issue my statement, instead of throwing this Exception?”
There are actually a number of reasons, starting with loss of transactional integrity. The …
[Read more]When examining MySQL configuration, we quite often want to know how various buffer sizes are used. This matters because some buffers (sort_buffer_size for example) are allocated to their full size immediately as soon as they are needed, but others are effectively a "max size" and the corresponding buffers are allocated only as big as needed (key_buffer_size). There are many examples of this. What about join_buffer_size?
I saw a my.cnf with a 128M join_buffer_size the other day and needed to research this quickly before I gave advice. The join buffer is a special case. Unlike many of the buffers that are allocated per-thread (i.e. per-connection), this one is allocated per-join-per-thread, in special cases. A join buffer is allocated to cache rows from each table in a join when the join can't use an index. This is because we know that the nested loop is effectively going to do a table scan on the inner table -- it has to, because there's no …
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I joined the number of those who have a public opinion on the
open core debate. Roberto Galoppini has graciously accepted to host a post on this topic in his Commercial Open Source Software blog. Please read it directly from there: Open to the core - The pragmatic freedom Enjoy! |
Remember the idea behind renaming Maria, the storage engine? People regularly get confused with Maria the storage engine, and MariaDB the database. We got a whole lot of good names, and here’s a short-listed amount of names (short-listed by Monty Program employees down to about 15), and now its up to YOU to help us choose what the new name should be. Quick, go take the survey.
Voting ends on Friday, July 9, 2010, at 23:59UTC.
The winner will be announced on the first day of OSCON on July 19 2010. The winner walks away with a …
[Read more]Back in January 2009, we found out that the Malaysian Government had saved about RM40 million using open source. In a little over a year, that number has been topped: over the past six years, the total costs savings are now quoted to be RM188.39 million (USD$58.54 million)! That’s a hell of a lot of money for software licenses, don’t you think?
Worth noting is that before the OSS Master Plan started, there were zero companies supporting OSS registered with the Ministry of Finance. Now more than half of the 4,000 companies do (53% is the quoted number). For more information, read the latest …
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On July 15th and 16th I will be in San Francisco for a few
meetings, and it will be my pleasure to meet the San Francisco MySQL User Group, where I
will talk about MySQL Sandbox. From there, I will continue to Portland, to attend the Community Leadership Forum and, of course OSCON, where I will have three talks: two in the main event, and one at the Intel booth. |
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