Hi, In this case grabTail would be quite useless, as one cannot really construct queues with it (ie. it would just force removing items from all namespaces that wouldn't even expire otherwise). The documentation also implies that there's a separate LRU list per namespace, which does make sense, but is not what's happening in production:
http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/memcache/MemcacheService.html#grabTail(int) "Grabs (atomically get and delete) items off the tail of LRU list. This can be used to implement queue system with high throughput and low latency, but low reliability. Current namespace should be set and not empty for the service. For each namespace memcache maintains a separate LRU list." Regards, Viktor On Feb 1, 9:22 pm, "Ikai L (Google)" <[email protected]> wrote: > I'll raise the issue with some other members of the team, but it seems like > this is working as expected. A memcache namespace is nothing more than a > prefix applied to a memcache key. There's no true partitioning mechanism > within memcache. grabTail simply returns the item that would be expired by > the LRU mechanism if memcache needed more space. There isn't a different > "queue" per namespace, only a "queue" for global expirations. > > > > > > On Mon, Feb 1, 2010 at 4:29 AM, phraktle <[email protected]> wrote: > > Hi, > > > On production, grabTail returns objects from other namespaces. This is > > a significant problem that > > makes grabTail (thus queue-like usage) unusable. > > > I filed this as a bug, with a very simple example here: > >http://code.google.com/p/googleappengine/issues/detail?id=2706 > > > Can you please look into this? I don't even see a workaround that I > > can implement in the meantime... > > > Thanks, > > Viktor > > > -- > > You received this message because you are subscribed to the Google Groups > > "Google App Engine for Java" group. > > To post to this group, send email to > > [email protected]. > > To unsubscribe from this group, send email to > > [email protected]<google-appengine-java%2B > > [email protected]> > > . > > For more options, visit this group at > >http://groups.google.com/group/google-appengine-java?hl=en. > > -- > Ikai Lan > Developer Programs Engineer, Google App > Enginehttp://googleappengine.blogspot.com|http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" 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-java?hl=en.
