aah alright. thanks Don for the clarification! kind regards, ingo
2010/7/14 Don Schwarz <schwa...@google.com>: > That is correct. You can not maintain state within the JVM and expect to > get any long-term persistence or coherency. > > You should use either memcache (which provides coherency) or the datastore > (which provides both). > > On Wed, Jul 14, 2010 at 3:38 PM, Ingo Jaeckel <ingo.jaec...@googlemail.com> > wrote: >> >> hello everyone, >> >> i just had a look into the documentation >> http://code.google.com/intl/de-DE/appengine/docs/java/runtime.html >> >> "App Engine uses multiple web servers to run your application, and >> automatically adjusts the number of servers it is using to handle >> requests reliably. A given request may be routed to any server, and it >> may not be the same server that handled a previous request from the >> same user." >> >> does this mean that there are n jvms on n servers running my >> application. thus if i want to collect profiling information about my >> server code i will always have to persist it in the db. it would not >> be sufficient just to hold it within the app (thus within the jvm). >> because i will have different application stats across the different >> servers running my application in parallel and independently.. >> >> can anyone confirm this claim? >> >> kind regards, >> ingo >> >> >> 2010/7/13 ingo <ingo.jaec...@googlemail.com>: >> > hello everyone, >> > >> > i want to collect some performance figures of my app on the server >> > side. but i do not want to persist them in the database, i only want >> > to collect them by changing the state of some class (i.e. changing >> > class members like number of requests, number of method calls, etc). i >> > want to read these values on the client side and display them in an >> > administration panel (or a profiler-like ui). >> > >> > but currently i think the application state is at least lost after >> > each new deployment. is this the only time the state is resetted? does >> > a jvm holding my application state run all the time between each >> > deployment? >> > >> > i have the same question regarding static members. i use singletons or >> > static variables on server side to make sure they are constructed only >> > once whenever their construction is expensive. so i want to make sure >> > that the jvm holding the instances is running for a very long time to >> > avoid reconstruction of them. however, it feels like the jvm is >> > restarted relatively often (due to very low load on my app maybe) and >> > thus the singletons are recreated during the jvm startup. >> > >> > kind regards, >> > ingo >> > >> > -- >> > 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. >> > >> > >> >> -- >> 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. >> > > -- > 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. > -- 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.
