We finally got the MySQL Connector/Python repositories reorganised on Launchpad. The following changes have been made:
The problemSometime back a member of the MySQL support team
informed us that the slaves are very sluggish, when he tried
to run a delete query on the master. "What may be the
problem?" we wondered. This is in RBR and its pretty
usual that we have slower slaves when using RBR as compared
to SBR. We requested for some more details and found that it
is something else. It's a problem when a lot of rows are
getting modified in a table without PRIMARY KEY.
"UPDATE t1 set a = a+1;" and other queries such as this are
generally found to make slaves sluggish if the table does
not have proper index. Is it a problem with the fact that a
lot of data is being transferred over the network? After all
the total amount of data that will be transferred over the
network will be more than twice (before and after image +
some header) the sizeof data that is modified. Could this be …
You can use pt-query-digest to process a MySQL slow query log and store historical values for review trend analysis into query_review_history table. According to its official documentation you can populate many columns in that table but there are other important ones such as ‘user’, ‘host’, ‘db’ which are not included by default. I will explain how to implement this.
Also the documentation says:
Any columns not mentioned above are inspected to see if they follow a certain naming convention. The column is special if the name ends with an underscore followed by any of these MAGIC_history_cols values:
pct|avt|cnt|sum|min|max|pct_95|stddev|median|rank
…
[Read more]When I kill a query or connection, whoever is running it gets a boring message about what happens. Wouldn’t it be fun and useful to be able to specify the error message the user should see? Imagine the possibilities: mysql KILL 10282, "Sorry, no cigar today. Try again tomorrow." Joking aside, relevant error messages would be great for all involved.
MySQL 5.1 added a long-needed feature: INFORMATION_SCHEMA tables for inspecting locks held and waited-for inside of InnoDB. With this addition, it became possible to figure out who is blocking whom. MySQL 5.5 changed a lot more things inside the server. One of the new features is improved metadata locking. This solves a lot of inconsistencies and bugs that were previously possible. The output of SHOW PROCESSLIST is also changed; instead of the venerable Locked status, there are more fine-grained status indicators such as Waiting for table metadata lock.
A few days I wrote a bit on my first results of comparing
MySQL with MongoDB as a Key-Value Store, something that has been
going on for way to long, but I am not finished yet. Last time I
used MySQL Embedded Library to bypass the MySQL Client Server
protocol to see what the overhead was, and the result was that it
is big (and again, note that the same networking was used with
MongoDB and I was also using Unix Domain Sockets, as well as
plain TCP/IP, so don't ask me to fix any network issues I might
have). Using Embedded Server with InnoDB was actually faster than
using MongoDB, some 3 times faster compared to using the client /
server protocol.
That one out of the way, I now wanted to see what I could get if
I used the storage engine that was fastest in Client / Server
mode, MEMORY. That took a while to fix, as to have an …
Taxonomy upgrade extras: galeraclusterMySQL Clusterchannelfail-overreplication
During and after Henriks great talk about Galera Cluster at the FrOSCon 2012 in St. Augustin we found 2 important things related to Galera Cluster for MySQL:
…Want to leverage the high-speed load utilities, distinctive memory caches, full text indexes, and other performance-enhancing mechanisms that MySQL offers to fuel today's critical business systems.
The authentic MySQL Performance Tuning course, in 4 days, teaches you to evaluate the MySQL architecture, learn to use the tools, configure the database for performance, tune application and SQL code, tune the server, examine the storage engines, assess the application architecture, and learn general tuning concepts.
You can take this course in one the following three ways:
Linuxcon is next week in San Diego and I will be speaking on The Proper Care and Feeding of a MySQL Database for Linux System Administrators. I will be in the Oracle booth with SWAG — and I hope to see you there!.
The Children’s pool used to be one of my favorite places to SCUBA dive before seals and sea lions took over. A nice two knot rip current was like an escalator out past the sea wall to some very interesting reefs off shore.
I was in San Diego a few weeks ago and can report the best pizza is at Fillipi’s in the near by Little Italy Section, the best food with a view is at C-level, and you should try to see the Cactus garden opposite the famous zoo.
…
For the week of August 24th, 2012: Everybody’s Preparing for OpenWorld Dispelling the Rumors of MySQL’s Impending Doom On Piracy of Design IOUG Podcast 24-AUG-2012 Rumors of MySQL’s Doom by Oracle / Design Piracy Subscribe to this Podcast (RSS) or … Continue reading →
