GAE: How many task per second is enough?

I'm using GAE and task queue. In queue.yaml file, I keep default setting: 5/s. 1 month ago I thought it's enough but now there are about 40-50 tasks in one queue so my application runs too slow.

I want to know how many tasks per second is 开发者_Go百科enough ? Can I change to 100/s ?

Thank you :)

Update:

My application gets data from some social networks, calculate and save to datastore. To over limit 30 seconds of GAE, I split this operation to tasks. I want to know the limit of GAE task queue before change and deploy to GAE :)

http://code.google.com/appengine/docs/python/taskqueue/overview.html#Quotas_and_Limits

or

http://code.google.com/appengine/docs/java/taskqueue/overview.html#Quotas_and_Limits

I'd highly recommend increasing the settings in steps to find your performance sweet spot. The number of tasks needed to run is obviously higher than 5/s but you don't know what's the proper number until you've tried running for a while, and heading straight to the top doesn't sound like a good idea.