currently there is no way to stop the running queries from client side. This could be an issue for the proxy (http://jan.kneschke.de/projects/mysql/mysql-proxy)

One of my biggest complaints about http+php+mysql is that when a browser stops any impending queries will run to completion on the mysqld side. Will mysqlnd allow these queries to be halted on script termination?

This is kind of mistake - I’m not going to Google HQ for MySQL Camp - I did not have visa so I could not go
The presentation you’re is from our discussion in Frankfut at International PHP Conference.

I wish you a good time at the Google HQ, for a developer like me it would be impressive
http://mysqlcamp.org/Session_PHP_mysqlnd

I hope you will post the presentation slides here afterwards.

It would be rather straightforward to implement the interface to MySQL’s XA implementation in PHP as the interface to XA in MySQL is standard SQL (unlike many other databases, which require native code or protocol-level calls to do the same thing):

http://dev.mysql.com/doc/refman/5.0/en/xa-statements.html

The issue is that PHP doesn’t have a transaction monitor, that I know of, so that would be the first thing someone would have to write, or “wrap” (many opensource transaction monitors exist in the Java world).

You can “fake” the protocol (and we do in the JDBC unit tests), but that doesn’t give you any recoverability if the application itself crashes without an actual logging transaction monitor, which then makes XA pretty much useless in real-world scenarios.

-Mark

Persistent connections were never bad thing per say but they had number of problems. Estabilishing new connection in many cases is not significantly more expensive than recycling connection (which also needs special command). Plus on Gbit ethernet connection establishment did not add too much latency anyway. On other hand large number of etablished connections has some overhead in scheduling, memory usage etc.

If pages are complicated there is very little win for persistant connections as connection creation will constitute very small proportion. For pages running single simple query which is frequently the case with AJAX it becomes significant.

Now about limiting number of persistent connections - Apache would never act as connection pooling daemon as connections can’t be shared between processes. Simply if there are too many persistent connection as connections are closed they would not be kept as persitent connections but closed at once.