Creating your first PersistenceManagerFactory is known to currently be expensive, but you should only be creating one of these per JVM (i.e. not per request). If you're seeing consistently long times to create just PersistenceManagers, please file an issue with a simple sample app that reproduces the problem.
On Thu, Sep 3, 2009 at 1:42 PM, Kurposkano <kurposk...@gmail.com> wrote: > > I am new to the Google Application Engine and have just started doing > some testing with a simple version of my client and server up and > running. In making my requests to the server, I have noticed a very > long wait time. So I decided to do some logging of the some of the > operations being done in my doPost. I found that it was taking approx. > 4.5 seconds to complete everything server side. This was quite > alarming to me, but I figured I had screwed something up so I started > doing some logging througout the code to find what areas were costing > me the most time. I found that the code that took me the longest was > creating my Persistence Manager (approx. 1.7 seconds!). This did not > make sense to me because it would seem that if it takes that long just > to get the manager up and running to do anything else, that all > requests server side would take a minimum of 2 seconds, if not much > longer. I am using JDO for my database setup, another first for me, so > I am wondering if I setup something wrong that is making it take such > a long time to get the manager. > > One of the reasons this struck me as odd is because of some text > written in the GAE docs (http://code.google.com/appengine/docs/java/ > runtime.html <http://code.google.com/appengine/docs/java/%0Aruntime.html>) > : > > "An application can process around 30 active dynamic requests > simultaneously. This means that an application whose average server- > side request processing time is 75 milliseconds can serve up to (1000 > ms/second / 75 ms/request) * 30 = 400 requests/second without > incurring any additional latency. Applications that are heavily CPU- > bound may incur some additional latency in long-running requests in > order to make room for other apps sharing the same servers. Requests > for static files are not affected by this limit." > > They talk about 75 ms average server-side request. Which of course I > just couldn't imagine given the 1.7 second average to get my > persistence manager. Any helpful knowledge on this all would be > greatly appreciated. > > > --~--~---------~--~----~------------~-------~--~----~ 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-java@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 -~----------~----~----~----~------~----~------~--~---
