Concurrency Issues when multiple users uses Portal (MySQL and PHP) We have set up a portal using Yii Framework in Apache, PHP and MySQL. In the portal, there is a feature to export the data in dbf format, the extract takes around 7 minutes, but in those 7 minutes no other user can do anything in portal, not even login.

All tables are in MyISAM Engine.

I cannot provide you the link as its in our internal server.

Server is 4core Xeon Processor with 32 GB Ram.
The framework calls somewhere, somehow the command mysqldump, and there you need to give him the --lock-tables=false option.