Is there an ideal number of network operations for iPhone OS?

Question

I'm using NSOperation and NSOperationQueue to handle all of my networking threads so my interface can remain responsive while handling data transfer over the internet. Currently, I've got my operation queue set to a maximum concurrent operation count of 5, and it seems to work well.

I'm wondering, though, if there is a more ideal number of concurrent network operations that would best maximize the available resources without choking the hardware. Are there any recommendations, or steps I might take to measure and find out for myself?

Answer 1

Given the iPhone (currently) runs a single core, I would guess 5 is around the right number.

But the only way to be sure would be to instrument it and find out what the usage looks like (CPU, Memory and Network). Network usage you could get based on the data transferred - but its hard to know what a reaspnable usage would be. I'm not sure if it is possible to get CPU/Memory statistics from the iPhone.

If you are doing large transfers, then more connections probably wont help much. If you are doing lots of small transfers, then more connections will help work around the back and forth of setting up and tearing down the connection.