由于我兄弟的主机要转向，个人博客 puzzlebird.com 今天转到了 goDaddy.com，每个月5美金，花了些时间搬站，不是很顺利，不过还是搞好了。
There was a strange problem with our ensembl server that usually the server becomes “inaccessible” in the morning, but when we tested a few times, the server works extremely well during the day. However, it becomes “inaccessible” again tomorrow morning.
The background for this issue that our user found local ensembl mirror sometimes inaccessible, but after a few refresh the pages comes out again. I realized the problem was caused by the small default value of max_connections in MySQL server, and the fact the ensembl uses DBI instead of Apache::DBI in the perl.startup script.
In the latest CVS code of ensembl, perl.startup file still uses “DBI” module, soI believe it will have potential performance issues on other mirror sites.
From: /dev/random
One thing I’ve found in common with all large
sites and that should be pretty obvious, is a PHP compiler cache and
some type of caching system. Some of the more popular ones are APC,
Bware Afterburner, Turck MMCache, and the Zend Accelerator. PHP caching
systems are easy to write and can speed up template calls a ton.
BSQ_stat component and module used to be the major tool to track the users of my sites, but Jack just kicked my ass because some of my MySQL processes took almost 100% CPU. Command “show processlists” stated my site is updating the BSQ_stats’s table, and the process seemed to hang and messed up the system. Apparently there’s bug in this component. Anyway, I removed this componets and uses only Google Analytics to track the traffic.
Solidot.org is a chinese clone of famous Slashdot.org. It is my favorite site to read geek IT news. Yesterday I read a “help request” from solidot.org for experienced Linux server expert. They encountered a problem to restore the MySQL dump to the new server. It appears to be text encoding problem.
A colleague asked me if I know how to limit the return data set in SQL (Oracle and MySQL). I did a search for Oracle, ya, it is correct to use ROWNUM internal variable to achieve that.
Ensembl has new releases every month. The databases names changed, so we have to re-grant all user privileges for all the 30-40 databases. That’s quite tedious.
So, here is something about me.
Expertises:
HPC Architecutre, Performance tuning (system/program profile),
Linux/Unix, Mac osX, Oracle, MySQL, Perl, C, SHELL, PHP, XML, Joomla
During bugzilla deployment, I found all the scripts hardcoded perl interpreter to be “/usr/bin/perl”. Our current environment uses perl at other locations and this makes deployment difficult if we are going to fixed all these 60+ scripts by hand. Hence, I wrote a fixPerl.sh to do this job.