On Monday I presented 3-hour tutorial "Linux and H/W optimizations for MySQL" at the MySQL Conference and Expo 2011, and published the slides at SlideShare.

Groklaw declares victory. Cloudera updates Hadoop distro. And more.

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“Tracking the open source news wires, so you don’t have to.”

# Groklaw claimed victory, will stop publishing new articles on May 16.

# Cloudera released version 3 of its Hadoop distribution.

# VoltDB released version 1.3 of its open source distributed in-memory database.

# Black Duck grew sales by 51% in Q1.

# eXo and Convertigo …

Update:

Commenter MarkR made a great point: if possible, use some packaging tools, to try to maintain proper dependencies, to the extent that is possible. Install from the source should be Plan B. So, try yum install MySQL-python first.

This is mostly for my own future reference. It’ll be icing on the cake if it helps you!

This is geared for CentOS or Red Hat. Use apt-get or other packaging tools for different flavours of Linux.

1. Get Python module setuptools called easy_install. I love easy_install, by the way, sort of like CPAN for Perl modules;
2. To install MySQLdb package, you would think easy_install MySQLdb would do. But that is not the case. I hope the developer would fix that. Instead, you need:

easy_install MySQL-python

3. If you have build errors, you may need:
yum install python-devel or yum …

Have you ever looked at your processlist and seen queries in the state “copying to tmp table” and then run an explain on it and noticed that the tmp table is being created on disk? Happens a lot with some servers and some workloads. Of course disk is much slower than RAM so this becomes a slow process and makes queries execute slower than they could if they were allowed to use RAM. So, one way to get this process to speed up (aside from tuning your queries which should be done first) is to create a tmpfs or ram-disk and let MySQL use that for it’s temp-table-on-disk creations. MySQL on Linux defaults to /tmp for the tmpdir location so this will need to be changed.

Here is how you get MySQL to use a 1G size tmpfs. How you size your tmpfs depends how much ram your system has and how much tmpdir space mysql needs for your workload. If you need more tmpdir space than you can make in a tmpfs mount then mysql allows multiple tmpdir locations …

I am reading and following examples in MySQL 5.1 Plugin Development. After compiling and moving a .so file (think DLL or Assembly file in Windows) into MySQL plugin directory, I got this message when I tried to create a UDF (User Defined Function):

mysql> create function udf_staticexample returns integer soname 'udf_staticexample.so';
ERROR 1126 (HY000): Can't open shared library 'udf_staticexample.so' (errno: 0 /usr/lib/mysql/plugin/udf_staticexample.so: failed to map segment from shared object: Permission denied)

This is caused by the fact that the .so shared object file is not in the right SELinux security context:

[root@asusfedora plugin]# ll -Z
lrwxrwxrwx. root root …

Longtime MySQL-er Lenz Grimmer

Lenz Grimmer

is leaving the MySQL side of the business to work in the Linux and Virtualization side of the Oracle business. He came from SuSE Linux and has retained interest in that area all the many years he helped make MySQL into the ubiquitous tool that it is. Lenz’s list of accomplishments is too long to note here and working with him on the MySQL Community Team has been a tremendous pleasure. He is not dropping off the face of the earth and will presenting at Collaborate 11 .

Please join me in wishing all the best for Lenz!

…

2011-06-26 update:

I am not sure if there are any changes in the latest make and gcc packages. Anyway, I noticed when run make, I encountered the message below:

make: g: Command not found
make: [qgen] Error 127 (ignored)

To fix this, find where gcc is at, then created a symbolic link g that points to gcc. All is well afterwards:
[root@ip-10-245-209-196 dbgen]# which gcc
/usr/bin/gcc
[root@ip-10-245-209-196 dbgen]# cd /usr/bin/
[root@ip-10-245-209-196 bin]# ln -s gcc g

End update
Recently I found myself doing some data loading benchmark testing with table partition. Data loading and storing for BI/DW/DSS stuff almost always involves data partitioning. SQL Server partition has a nice feature called partition switch, where you can swap data in and out of a partitioned table. …

Time is flying by so fast, it sure doesn’t seem like it was last year I was blogging about how Android is for real. Well, let me reiterate … Android is for real. The reason I say that and stress that is despite its success, we see a variety of legal threats, accusations and actual lawsuits to come flying at Android as fast as it is growing in the market.

Still, we seem to be able to fairly easily find agreement among vendors, developers and users that Android development is not slowing down, that legal maneuvering will not pave a path to success or that any ruling or action will take Android-based phones out of consumers’ hands. This is not to say that Android faces significant challenges: real fragmentation and version overload; a software development pace that may be too fast for handset makers or consumers; innovation from rivals …

Red Hat grows revenue 20%+. Google withholding Honeycomb source code. And more.

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“Tracking the open source news wires, so you don’t have to.”

# Red Hat reported Q4 revenue up 25% to $245m, FY revenue up 22% to $909m

# Google is withholding the source code to Honeycomb for the foreseeable future.

# Rick Clark explained why he left Rackspace amid concerns that the company is exerting too much control over OpenStack.

# DataStax …

Paranoid Android. Canonical and Gnome. A new OSI. And more.

Paranoid Android
If you are interested in the potential violation of the GPL by the Android kernel you have probably already immersed yourself in the numerous blog posts published on the topic. If not, start with Sean Hogle’s analysis or Bradley M Kuhn’s overview of the original allegations and work backwards from there, not forgetting a detour for the obligatory Microsoft connection. Linus Torvalds said claim “seems totally bogus”. In the meantime, Microsoft …