Hi all,

I'm looking for a good way to solve the following problem:

Clients connect to a machine, login and wait for messages. These messages (basically strings) are stored in a database with the appropriate client id. Each client request is forked by the main perl process. So each process should check for messages in the database (e.g. 5x per second).

When there are many clients connected, this causes a heavy load on the database. I am looking for a good solution for this.

The best I can come up with is this:
The main process which accepts clients forks another process which selects the unique client ids from the message database. This process signals the corresponding client process that there are messages waiting. After this, the corresponding process will also query the database to get the waiting messages.

This way, only one process actively queries the database. The difficulty in this approach is the process setup and fork management. The main process knows it's childs and thus the connected client, but the database poller process does not.

Any ideas/suggestions/improvements?

Marcello

In reply to Database poller by Marcello

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