Q:

crawler on appengine

i want to run a program continiously on appengine.This program will automatically crawl some website continiously and store the data into its database.Is it possible for the program to
continiously keep doing it on appengine?Or will appengine kill the process?
Note:The website which will be crawled is not stored on appengine

A:

i want to run a program continiously
  on appengine.

Can't.
The closest you can get is background-running scheduled tasks that last no more than 30 seconds:

Notably, this means that the lifetime
  of a single task's execution is
  limited to 30 seconds. If your task's
  execution nears the 30 second limit,
  App Engine will raise an exception
  which you may catch and then quickly
  save your work or log process.

