I believe I am experiencing a similar issue. I am using two applications with identical (search engine) code servicing searches against indexes stored in Datastore. To speed up access to index blobs I am using memcache.
Experimentally, I enabled billing for one of these apps to check if I would get better performance from that app. Unfortunately -- I am getting *worse* performance from the billing enabled app as it does not seem to be able to successfully memcache my blobs. On Dec 15, 3:17 pm, "Ikai L (Google)" <[email protected]> wrote: > Martin, > > Let us know if there's a pattern. I'd like to be able to track this down. > > On Mon, Dec 14, 2009 at 2:58 AM, Martin Caslavsky <[email protected]>wrote: > > > > > There are only several objects in the cache (up to 10), each about > > 10kb. But there is also a bigger one (about 260kb) which I suspect of > > source of problems. > > > I am afraid I am not able to reproduce the problem. > > Dec 7: 2600 pageviews, cache occasionally does not work (at least one > > time started to work again after redeploy) > > Dec 8: 1000 pageviews, cache worked ok > > Dec 9: 700 pageviews, cache occasionally does not work > > > Martin > > > On Dec 10, 8:15 pm, "Ikai L (Google)" <[email protected]> wrote: > > > There are limits to the size of your cache, but Memcache LRU expiration > > > should be pushing out older items, not newer items that are going into > > the > > > cache. Also, a deploy should not be causing this to occur. > > > > What steps can be taken to reproduce this? What are the size of the > > blobs, > > > and what load can I use to cause this to happen? > > > > On Wed, Dec 9, 2009 at 4:04 PM, Martin Caslavsky <[email protected] > > >wrote: > > > > > Yes, cache maps Strings (URLs) to byte[] blobs (RSS feed content). > > > > > Martin > > > > > On Dec 10, 12:13 am, "Ikai L (Google)" <[email protected]> wrote: > > > > > What kind of objects are you storing the cache? Are you storing large > > > > binary > > > > > objects? > > > > > > On Tue, Dec 8, 2009 at 12:23 AM, Martin Caslavsky < > > [email protected] > > > > >wrote: > > > > > > > Sorry, it is dmczum. > > > > > > FYI redeploy of the app helps for a few hours. > > > > > > > Martin > > > > > > > On Dec 8, 2:20 am, "Ikai L (Google)" <[email protected]> wrote: > > > > > > > Martin, > > > > > > > > Can you provide your app ID? I'm not able to look up czumdm. > > > > > > > > On Sun, Dec 6, 2009 at 4:40 PM, Martin Caslavsky < > > > > [email protected] > > > > > > >wrote: > > > > > > > > > Hi, > > > > > > > > > my java app (czumdm) was over quota, so I enabled billing. > > First > > > > > > > > request was processed at 12-06 04:10PM 11.559. App worked > > correctly > > > > -- > > > > > > > > most request was processed from JCache (logged as "execute() > > > > > > > > skipping") and several request was processed directly (logged > > as > > > > > > > > "execute()"). > > > > > > > > > But as of 12-06 04:15PM 49.099 the method call > > > > cache.containsKey(key) > > > > > > > > returns false, thus no request is processed from cache! > > > > > > > > > Cache statistics shows some cached objects (correct) but hits > > count > > > > is > > > > > > > > stalled and miss count is increasing (weird). > > > > > > > > > Greets > > > > > > > > Martin > > > > > > > > > -- > > > > > > > > > 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%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[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 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]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > > > > <google-appengine-java%[email protected]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[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 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]<google-appengine-java%[email protected]> > > <google-appengine-java%[email protected]<google-appengine-java%[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 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]<google-appengine-java%[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 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.
