No, there's no control over this. It's a bit of an overoptimization right now, wouldn't you say? I'd put it into production first before seeing how much I'd need it.
On Thu, Sep 16, 2010 at 9:36 AM, Maxim Veksler <[email protected]> wrote: > Thank you Ikai. > > It's perfectly clear the JVM's spin up / down (and to the sides at some > strange corner cases :) > > Is it possible to share the amount of threads a typical JVM running on up > appengine is configured to launch? > That would help me plan better, because if I have a class that eats 0.5MB > of heap (theoretically, I'm more like 1-5k) . Then if each JVM has a maximum > of 2000 threads it's OK but if each JVM get's 20000 threads then this design > won't do. > > Appreciate your comments. > > Thank you, > Maxim. > > On Thu, Sep 16, 2010 at 4:07 PM, Ikai Lan (Google) < > [email protected] <ikai.l%[email protected]>> wrote: > >> You can store data in ThreadLocal as a cache, but it will be extremely >> volatile, especially if we spin up/spin down instances. It's fine to use >> this to cache data that you can easily regenerate. Just be aware that if you >> hit memory limits, we will cull and restart that instance. >> >> >> On Thu, Sep 16, 2010 at 12:50 PM, Francois Masurel <[email protected]>wrote: >> >>> Each app instance runs in its own JVM. So it should be safe to cache >>> data in ThreadLocal. >>> >>> On 16 sep, 09:08, Maxim Veksler <[email protected]> wrote: >>> > I would like to cache a not thread safe object, I'm hoping to improve >>> > performance by caching it instead of instantiating new instance per >>> request. >>> > >>> > Thanks, >>> > Maxim. >>> > >>> > On Thu, Sep 16, 2010 at 8:12 AM, Guillaume Laforge <[email protected] >>> >wrote: >>> > >>> > >>> > >>> > > What kind of data or information do you want to share through >>> thread-locals >>> > > between threads/requests? >>> > >>> > > On Thu, Sep 16, 2010 at 08:04, Maxim Veksler <[email protected]> >>> wrote: >>> > >>> > >> I didn't say multi threaded. >>> > >>> > >> ThreadLocal gives access to the cached object of the current thread. >>> > >> I'm doing an assumption here that appengine/j is implemented with >>> thread >>> > >> per incoming request. >>> > >>> > >> What I would like to know is if these threads are recycled (in which >>> case >>> > >> ThreadLocal is a good approach) or not. >>> > >>> > >> Thanks, >>> > >> Maxim. >>> > >>> > >> On Thu, Sep 16, 2010 at 6:17 AM, Didier Durand < >>> [email protected]>wrote: >>> > >>> > >>> Hi Maxim, >>> > >>> > >>> Multi-threading is not the way to go under GAEJ, see >>> > >>>http://code.google.com/appe< >>> http://code.google.com/appengine/docs/java/runtime.html#The_Sandbox> >>> > >>> > >> *I didn't say multi threaded. * >>> > >>> > >> ngine/docs/java/runtime.html#The_Sandbox< >>> http://code.google.com/appengine/docs/java/runtime.html#The_Sandbox> >>> > >>> > >>> The right way to go is Tasks: >>> > >>>http://code.google.com/appengine/docs/java/taskqueue/overview.html >>> > >>> > >>> regards >>> > >>> > >>> didier >>> > >>> > >>> On Sep 15, 2:00 pm, Maxim Veksler <[email protected]> wrote: >>> > >>> > Hello, >>> > >>> > >>> > I'm wondering (after some internal discussion we had) is using >>> > >>> ThreadLocal >>> > >>> > for applications running on the AppEngine is performance >>> beneficial ? >>> > >>> > >>> > For this to work AppEngine should recycle threads, right? >>> > >>> > >>> > Another question is how many threads does the appengine allows >>> per JVM >>> > >>> ? >>> > >>> > Such ThreadLocal based approach would (probably) be inefficient >>> if the >>> > >>> JVM >>> > >>> > allowed 20000 threads. >>> > >>> > >>> > Help is appreciated. >>> > >>> > Maxim. >>> > >>> > >>> -- >>> > >>> 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%2B >>> [email protected]> >>> > >>> . >>> > >>> 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 >>> > >> [email protected]. >>> > >> To unsubscribe from this group, send email to >>> > >> [email protected]<google-appengine-java%[email protected]><google-appengine-java%2B >>> [email protected]> >>> > >> . >>> > >> For more options, visit this group at >>> > >>http://groups.google.com/group/google-appengine-java?hl=en. >>> > >>> > > -- >>> > > Guillaume Laforge >>> > > Groovy Project Manager >>> > > Head of Groovy Development at SpringSource >>> > >http://www.springsource.com/g2one >>> > >>> > > -- >>> > > 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%2B >>> [email protected]> >>> > > . >>> > > 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 >>> [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. >>> >>> >> -- >> 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. >> > > -- > 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. > -- 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.
