Memcache data is never persisted to disk, so in the event of a Memcache server restart, you will lose all the data in Memcache. In addition, Memcache evicts items based on an LRU cache: if you don't use data for a while and space is needed, the item will be removed from your cache to allow for your new items. You can read more about Memcache here:
http://code.google.com/p/memcached/wiki/FAQ <http://code.google.com/p/memcached/wiki/FAQ> On Sat, Apr 3, 2010 at 12:59 AM, aswath satrasala < aswath.satras...@gmail.com> wrote: > Hello Ikai, > I am interested in Sequences, sequence starting from a initial value and > increments. > Can you little bit elaborate here on what is the risk with volatile here > when using memcache. > > Regards > -Aswath > > > On Sat, Mar 6, 2010 at 1:05 AM, Ikai L (Google) <ika...@google.com> wrote: > >> Have you looked into Memcache's INCR? >> >> >> http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/memcache/MemcacheService.html#increment(java.lang.Object<http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/memcache/MemcacheService.html#increment%28java.lang.Object> >> , >> long) >> >> This'll do it atomically, but you run the risk of it being volatile, >> so you'll have to account for that in your client code. >> >> On Tue, Mar 2, 2010 at 11:40 PM, legendlink <gregc...@gmail.com> wrote: >> > hi, i wanted to have a sequence generator that increments by x value >> > everytime it generates a value. if i would create the sequence >> > generator by using the datastore, it is likely that data contention >> > would occurr if there is high access times. >> > >> > i have looked into the sample code of max ross in the google code >> > repository (SequenceExamplesJDO.java) and think this is limited to >> > increment by 1 only and not increment by x value. >> > >> > if sharding technique is used, my concern is that i might not get the >> > right sequence. >> > >> > what is the best/elegant way of doing sequence generator that >> > increments x value? >> > >> > -- >> > 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 >> http://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 >> 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 http://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 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.
