Two posts ago http://groups.google.com/group/google-appengine/browse_thread/thread/e5d6a1eae6080878/73a99164d7899859#73a99164d7899859 deal with the same issue. it seems like AppEngine is evicting sooner than you might expect... still no formal answer
On Dec 12, 3:33 pm, Tomas Alaeus <[email protected]> wrote: > 1. The time you specify when putting memcache entities is the maximum > lifetime. There is no guarantee that the memcache will hold its > contents for any period of time, they can be evicted immediately or > after a month, you have no way of knowing that. > > 2. Not that I know of. Part of the memcache can be flushed, or all of > it, at a time. So I don't think there is an easy way to implement it > either. Besides, since the memcache is stored in volatile memory the > "flush" can be triggered by a machine shutting down. In that case it > would be hard to know immediately which entities were removed. > > You should always make the code work even if the memcache always > return null. Easiest is to populate the memcache when a request > fetches a null entity, so it always have something to fall back on. > > On 12 Dec, 14:24, Sharma Anil <[email protected]> wrote: > > > > > > > > > I have implemented the following on GAE. > > > 1. Fetch all entities in a Kind and identify the last updated > > entity. > > 2. Set the memcache with a key and a property from the entity from > > step one with specifying 6 hours longevity > > 3. Log the information and status > > 4. Define a cron job handle to do all steps 1, 2 and 3, in every 4 > > hours > > > Result: Works fine most of the time. > > Problem: Memcache entry does not exist for the duration set for > > it. > > > Question: 1. Is there any way to ensure Memcache key-value pair > > for a defined time ? > > 2. Is there anyway to get a message from GAE on > > forced Memcache flush out ? -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
