Shell Tips !

Here is a quick picture about the impact of MySQL indexes misuse. At work, our developers made a new release of their search engine using MySQL fulltext indexes, unfortunately they didn’t implement it correctly. The impact was a huge load on all our database servers. To find the trouble, I had to redirect the SQL search flow to a specific server and check for the slow queries then reproduce it with EXPLAIN. Don’t need a long time to find that the search query did an invalid usage of the fulltext index and the “Match / Against” syntax. In fact, the fulltext index was a multiple column fulltext index, in such case you have to specify ALL the column present in your index, else the index won’t be used by MySQL…

If you are a PHP developer or a LAMP server admin you probably have already heard about the Zend Platform. After some test and configure/tunning step, we deployed this solution on a heavy loaded production server running with Apache 2.x, PHP 4.4.x, MySQL Client 5.x.

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You probably already ask you : “which filesystem can I use on my web servers or database server ?” Usually you will use the well know Ext3-fs but what about the others ?

I will just try to give you some clue about some other common filesystems. The filesystem aspect of your server is really important and your choice will vary with your running application. As exemple, a mail server will have more performances with a Reiserfs filesystem than with Ext3-fs.

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