There's very little cost to "connecting" to the datastore. If this is an issue, I'd look at the low-level API for anything that could be a warm-up request. The expensive part of this is initializing your PersistenceManagerFactory/EntityManagerFactory, not establishing a datastore connection.
On Tue, Jun 1, 2010 at 8:12 PM, Rahul Juneja <rahul.jun...@gmail.com> wrote: > Ikai, > The problem is that i am not sure when the values in the cache will be > accessed. but anyways i have implemented it in such a way that if the value > is not found in cache it goes to database to fetch it, but another issue > there is that if you are making the database connection first time after the > new jvm instance has been kicked off as it happens in Appengine, db > connection takes a while, sometimes around 6-7 seconds, which is kind of > slow. > > Nicolas, > Thats the reason i am fetching the data if not found in cache. > > > Thanks, > Rahul > > ---------------------------------------------------------- > Rahul Juneja > http://techlabs.thoughtclicks.com > > > On Tue, Jun 1, 2010 at 9:41 PM, Ikai L (Google) <ika...@google.com> wrote: > >> The items will get flushed if they are not getting used. If you're using >> items once every 24 hours ... you probably do not need a cache. Use the >> datastore instead. Rather than prevent the items from being flushed, build >> the ability to regenerate the cache into your system or don't even bother >> with Memcache. >> >> On Tue, Jun 1, 2010 at 6:24 PM, Rahul Juneja <rahul.jun...@gmail.com>wrote: >> >>> Ikai, >>> >>> I think you are right that the cache values are expiring via LRU as >>> sometimes only some elements of the cache are flushed. >>> But the question is my cache only has 20-30 entries and out of that 10 >>> least recently used entries are being flushed. Is there any way i can >>> prevent this flushing as i don't want to flush if the cache is so small >>> instead i want the cache only to flush LRU elements when the cache grows in >>> size to maybe 100,000 entries. >>> >>> Any clues ? >>> >>> Thanks, >>> Rahul >>> >>> ---------------------------------------------------------- >>> Rahul Juneja >>> http://techlabs.thoughtclicks.com >>> >>> >>> On Tue, Jun 1, 2010 at 6:56 PM, Ikai L (Google) <ika...@google.com>wrote: >>> >>>> No, there isn't a default expiration. How are you setting values to the >>>> cache? Could you be expiring the items via LRU? That is - you're not using >>>> the items in the cache, instead setting other items and pushing the older, >>>> unused items out? >>>> >>>> On Wed, May 26, 2010 at 6:43 PM, Rahul <rahul.jun...@gmail.com> wrote: >>>> >>>>> I have a memcache and not to mention it does live between different >>>>> jvm instances when new jvm instances starts, i can access the cache >>>>> but once a while i don't find any values in cache and this happened >>>>> twice in last 24 hours. Is there any default expiration which is less >>>>> then 24-48 hours which i am not aware of. >>>>> >>>>> Any help or pointers on this is appreciated. >>>>> >>>>> Thanks, >>>>> Rahul >>>>> >>>>> -- >>>>> 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 >>>>> google-appengine-j...@googlegroups.com. >>>>> To unsubscribe from this group, send email to >>>>> google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> >>>>> . >>>>> For more options, visit this group at >>>>> http://groups.google.com/group/google-appengine-java?hl=en. >>>>> >>>>> >>>> >>>> >>>> -- >>>> Ikai Lan >>>> Developer Programs Engineer, Google App Engine >>>> Blog: http://googleappengine.blogspot.com >>>> Twitter: http://twitter.com/app_engine >>>> Reddit: http://www.reddit.com/r/appengine >>>> >>>> -- >>>> 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 >>>> google-appengine-j...@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> >>>> . >>>> For more options, visit this group at >>>> http://groups.google.com/group/google-appengine-java?hl=en. >>>> >>> >>> -- >>> 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 >>> google-appengine-j...@googlegroups.com. >>> To unsubscribe from this group, send email to >>> google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> >>> . >>> For more options, visit this group at >>> http://groups.google.com/group/google-appengine-java?hl=en. >>> >> >> >> >> -- >> Ikai Lan >> Developer Programs Engineer, Google App Engine >> Blog: http://googleappengine.blogspot.com >> Twitter: http://twitter.com/app_engine >> Reddit: http://www.reddit.com/r/appengine >> >> -- >> 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 >> google-appengine-j...@googlegroups.com. >> To unsubscribe from this group, send email to >> google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> >> . >> For more options, visit this group at >> http://groups.google.com/group/google-appengine-java?hl=en. >> > > -- > 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 > google-appengine-j...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > -- Ikai Lan Developer Programs Engineer, Google App Engine Blog: http://googleappengine.blogspot.com Twitter: http://twitter.com/app_engine Reddit: http://www.reddit.com/r/appengine -- 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 google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
