Subject RE: [firebird-support] Performance of events
Author Jerry Sands

I make heavy use of events. I have a Point of Sale system that uses events to alert other POS stations of changes in invoices, etc. The events also trigger the program that caused the event to refresh its datasets as well. I am actually using a dynamic event so to speak. The event name ends in an invoice number so any stations with the same invoice number open would get change events and keep themselves refreshed with the latest changes. It all works very well, overhead has never been any problem. I am using IBObjects which handle events very well. My understanding is other access tools had problems with event handling in the past and I don’t know if those problems are resolved or not. I have used these events from a single program connected to 20 + databases in a wide area network. There are some things I did not use events on before I started using IBObjects that I will eventually re-write to use them.

Hope that helps.

Jerry Sands

From: [] On Behalf Of Daniel Albuschat
Sent: Tuesday, December 15, 2009 6:15 AM
Subject: [firebird-support] Performance of events


I'm currently widely adopting the usage of events to realize a live
update on all clients when data has been changed from another client.
Does anybody have experience with posting and registering for a lot of
events and it's impacts?
The current usage of event is one posted event every few seconds, with
at least one to five clients listening for that event. That's not much
and I am planning to add much more "event-traffic", but I've noticed
that fbserver utilized the CPU to 100% today and yesterday and I'm not
sure, why. Are events something meant to be used rarely, or is
something like 10 posted events per second with 100 different clients
listening to potentially hundreds of events per connection feasible?
Could it potentially slow down the server because of dificulties
regarding transaction isolation?

Any hint, suggestion or experience would be highly appreciated.


Daniel Albuschat

eat(this); // delicious suicide

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