Re: Tapestry in GAE
On Mon, Jun 7, 2010 at 20:38, Howard Lewis Ship hls...@gmail.com wrote: That's interesting, that GAE shuts down your instances. Yes, its a big issue for some projects, so now google is working to impoement support for dedicated JVMs: The work is in the progress but we should wait for the results. Here is the news from the Google I/O. See starting from 44:12 http://code.google.com/events/io/2010/sessions/whats-hot-in-java-for-app-engine.html - Dedicated JVMs - Will cost money There's a bit of Tapestry based on the idea that the application is long running, so it's OK if it takes a moment to start up initially. Under GAE that's not the case ... perhaps Tapestry under GAE should be even a bit lazier about loading and instantiating. When GAE shuts down the instance, is it undeploying the WAR? I don't know. I'm not even sure whether there is a WAR, actually. I can see in logs that sometime GAE starts a new JVM process, but sometimes I see just Tapestry initialization with building services through AppModule. All told, I think the most significant amount of time spent starting up a T5 app is the initial load of all those classes. I can see these during the Selenium integration tests, where the second test app to start up (all within the same JVM) is much faster because all the framework classes have already been loaded. According to starting log request (see below), it takes ~13 seconds (from 11.00.02.201 to 11.00.15.399) for tapestry to build my services and render index page. Compare it to 236 milliseconds total (!) for the second request to the same page (when JMV is warm and caching is in scene). The other time (~ 4,8 seconds) is some generic infrastructure startup (from 10:59:57.418 to 11.00.02.201). This time is the same for non-tapestry starting requests. I just realized I've never turned on debug logging level for tapestry google code in production, will do this and see. 1. 06-07 10:59PM 57.418 / 200 18215ms 20740cpu_ms 304api_cpu_ms 3kb Mozilla/5.0 (Windows; U; Windows NT 6.0; ru; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 ( .NET CLR 3.5.30729),gzip(gfe) 109.95.252.98 - dmitry.gusev [07/Jun/2010:23:00:15 -0700] GET / HTTP/1.1 200 3763 http://ping-service.appspot.com/; Mozilla/5.0 (Windows; U; Windows NT 6.0; ru; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 ( .NET CLR 3.5.30729),gzip(gfe) 2. I 06-07 11:00PM 00.033 dmitrygusev.tapestry5.gae.ProfilingDelegate makeSyncCall: GAE/S memcache.Get: -24- dmitrygusev.tapestry5.gae.ProfilingDelegate.buildStackTrace:37 dm 3. I 06-07 11:00PM 00.065 dmitrygusev.tapestry5.gae.ProfilingDelegate makeSyncCall: GAE/S memcache.Get: -21- dmitrygusev.tapestry5.gae.ProfilingDelegate.buildStackTrace:37 dm 4. D 06-07 11:00PM 02.201 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'LazyJPATransactionManager'. 5. D 06-07 11:00PM 03.220 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'TimingFilter'. 6. D 06-07 11:00PM 03.225 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'Utf8Filter'. 7. D 06-07 11:00PM 03.255 org.apache.tapestry5.ioc.internal.ServiceBuilderMethodInvoker createObject: Invoking method dmitrygusev.ping.services.AppModule.buildUtf8Filter(Reques 8. D 06-07 11:00PM 03.261 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'Application'. 9. D 06-07 11:00PM 03.263 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'ScheduleDAO'. 10. D 06-07 11:00PM 03.318 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'AccountDAO'. 11. D 06-07 11:00PM 03.342 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'JobDAO'. 12. D 06-07 11:00PM 03.371 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'RefDAO'. 13. D 06-07 11:00PM 03.423 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'JobResultDAO'. 14. D 06-07 11:00PM 03.459 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'GAEHelper'. 15. D 06-07 11:00PM 03.461 org.apache.tapestry5.ioc.internal.ServiceBuilderMethodInvoker createObject: Invoking method dmitrygusev.ping.services.AppModule.buildGAEHelper(Request 16. D 06-07 11:00PM 03.472 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'JobExecutor'. 17. D 06-07 11:00PM 03.477 org.apache.tapestry5.ioc.internal.ConstructorServiceCreator createObject: Invoking constructor dmitrygusev.ping.services.JobExecutor() (at JobExecutor 18. D 06-07 11:00PM 03.479 org.apache.tapestry5.ioc.internal.ModuleImpl create: Creating service 'Mailer'. 19. D 06-07 11:00PM 03.489 org.apache.tapestry5.ioc.internal.ConstructorServiceCreator createObject: Invoking constructor dmitrygusev.ping.services.Mailer() (at Mailer.java:17) 20. D 06-07 11:00PM 03.521 org.apache.tapestry5.ioc.internal.ModuleImpl
Re: Tapestry in GAE
Btw, I also found that tynamo's implementation of JPATransactionManager
doesn't fit well when using DAO-level caching.
Assume I have AccountDAO interface:
public interface AccountDAO {
@CommitAfter
public Account getAccount();
}
AccountDAOImpl is an implementation of this interface that communicated to
datastore.
And also I have AccountDAOImplCache extending AccountDAOImpl which caches
database response in two levels: 1) local memory 2) memcache.
In order this to work in GAE I need @CommitAfter annotation (because in one
transaction I can't work with entities of different entity groups, and
normally you do have such code).
Now if AccountDAOImplCache can provide value from cache you wont use DB at
all, but JPATransactionManager will force to commit and begin new
transaction. This is heavy. Also if during request handling you don't have
any DB communications default JPATransactionManager implementation will
begin/rollback transaction around request, which is not required but by
design.
I had to rewrite this implementation and begin new transaction only if some
datastore query creating (I did a wrapper for EM).
This also saved me a lot response time.
On Tue, Jun 8, 2010 at 10:22, Dmitry Gusev dmitry.gu...@gmail.com wrote:
On Mon, Jun 7, 2010 at 20:38, Howard Lewis Ship hls...@gmail.com wrote:
That's interesting, that GAE shuts down your instances.
Yes, its a big issue for some projects, so now google is working to
impoement support for dedicated JVMs:
The work is in the progress but we should wait for the results. Here is the
news from
the Google I/O. See starting from 44:12
http://code.google.com/events/io/2010/sessions/whats-hot-in-java-for-app-engine.html
- Dedicated JVMs
- Will cost money
There's a bit of
Tapestry based on the idea that the application is long running, so it's
OK
if it takes a moment to start up initially. Under GAE that's not the case
... perhaps Tapestry under GAE should be even a bit lazier about loading
and
instantiating.
When GAE shuts down the instance, is it undeploying the WAR?
I don't know. I'm not even sure whether there is a WAR, actually.
I can see in logs that sometime GAE starts a new JVM process, but sometimes
I see just Tapestry initialization with building services through AppModule.
All told, I
think the most significant amount of time spent starting up a T5 app is
the
initial load of all those classes. I can see these during the Selenium
integration tests, where the second test app to start up (all within the
same JVM) is much faster because all the framework classes have already
been
loaded.
According to starting log request (see below), it takes ~13 seconds (from
11.00.02.201 to 11.00.15.399) for tapestry to build my services and render
index page. Compare it to 236 milliseconds total (!) for the second request
to the same page (when JMV is warm and caching is in scene).
The other time (~ 4,8 seconds) is some generic infrastructure startup (from
10:59:57.418 to 11.00.02.201). This time is the same for non-tapestry
starting requests.
I just realized I've never turned on debug logging level for tapestry
google code in production, will do this and see.
1. 06-07 10:59PM 57.418 / 200 18215ms 20740cpu_ms 304api_cpu_ms 3kb
Mozilla/5.0
(Windows; U; Windows NT 6.0; ru; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 (
.NET CLR 3.5.30729),gzip(gfe)
109.95.252.98 - dmitry.gusev [07/Jun/2010:23:00:15 -0700] GET / HTTP/1.1
200 3763 http://ping-service.appspot.com/; Mozilla/5.0 (Windows; U; Windows
NT 6.0; ru; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 ( .NET CLR
3.5.30729),gzip(gfe)
2. I 06-07 11:00PM 00.033 dmitrygusev.tapestry5.gae.ProfilingDelegate
makeSyncCall: GAE/S memcache.Get: -24-
dmitrygusev.tapestry5.gae.ProfilingDelegate.buildStackTrace:37 dm
3. I 06-07 11:00PM 00.065 dmitrygusev.tapestry5.gae.ProfilingDelegate
makeSyncCall: GAE/S memcache.Get: -21-
dmitrygusev.tapestry5.gae.ProfilingDelegate.buildStackTrace:37 dm
4. D 06-07 11:00PM 02.201 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'LazyJPATransactionManager'.
5. D 06-07 11:00PM 03.220 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'TimingFilter'.
6. D 06-07 11:00PM 03.225 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'Utf8Filter'.
7. D 06-07 11:00PM 03.255
org.apache.tapestry5.ioc.internal.ServiceBuilderMethodInvoker
createObject: Invoking method
dmitrygusev.ping.services.AppModule.buildUtf8Filter(Reques
8. D 06-07 11:00PM 03.261 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'Application'.
9. D 06-07 11:00PM 03.263 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'ScheduleDAO'.
10. D 06-07 11:00PM 03.318 org.apache.tapestry5.ioc.internal.ModuleImpl
create: Creating service 'AccountDAO'.
11. D 06-07 11:00PM
Tapestry in GAE
That's interesting, that GAE shuts down your instances. There's a bit of Tapestry based on the idea that the application is long running, so it's OK if it takes a moment to start up initially. Under GAE that's not the case ... perhaps Tapestry under GAE should be even a bit lazier about loading and instantiating. When GAE shuts down the instance, is it undeploying the WAR? All told, I think the most significant amount of time spent starting up a T5 app is the initial load of all those classes. I can see these during the Selenium integration tests, where the second test app to start up (all within the same JVM) is much faster because all the framework classes have already been loaded. On Mon, Jun 7, 2010 at 7:01 AM, Thiago H. de Paula Figueiredo thiag...@gmail.com wrote: On Mon, 07 Jun 2010 10:42:52 -0300, Dmitry Gusev dmitry.gu...@gmail.com wrote: This is exactly what I mean, I don't want tapestry to load even once for some requests. GAE shutdown/startup instances very often (one new instance per ~3 minues) and this consumes additional resources. Oops, I forgot this GAE characteristic and what you said makes sense now. :) -- Thiago H. de Paula Figueiredo Independent Java, Apache Tapestry 5 and Hibernate consultant, developer, and instructor Owner, Ars Machina Tecnologia da Informação Ltda. http://www.arsmachina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org -- Howard M. Lewis Ship Creator of Apache Tapestry The source for Tapestry training, mentoring and support. Contact me to learn how I can get you up and productive in Tapestry fast! (971) 678-5210 http://howardlewisship.com
Re: Tapestry in GAE
http://www.answercow.com/2010/03/google-app-engine-cold-start-guide-for.html is an interesting read on how much startup time is spent on several java libraries at GAE On Mon, Jun 7, 2010 at 19:38, Howard Lewis Ship hls...@gmail.com wrote: That's interesting, that GAE shuts down your instances. There's a bit of Tapestry based on the idea that the application is long running, so it's OK if it takes a moment to start up initially. Under GAE that's not the case ... perhaps Tapestry under GAE should be even a bit lazier about loading and instantiating. When GAE shuts down the instance, is it undeploying the WAR? All told, I think the most significant amount of time spent starting up a T5 app is the initial load of all those classes. I can see these during the Selenium integration tests, where the second test app to start up (all within the same JVM) is much faster because all the framework classes have already been loaded. On Mon, Jun 7, 2010 at 7:01 AM, Thiago H. de Paula Figueiredo thiag...@gmail.com wrote: On Mon, 07 Jun 2010 10:42:52 -0300, Dmitry Gusev dmitry.gu...@gmail.com wrote: This is exactly what I mean, I don't want tapestry to load even once for some requests. GAE shutdown/startup instances very often (one new instance per ~3 minues) and this consumes additional resources. Oops, I forgot this GAE characteristic and what you said makes sense now. :) -- Thiago H. de Paula Figueiredo Independent Java, Apache Tapestry 5 and Hibernate consultant, developer, and instructor Owner, Ars Machina Tecnologia da Informação Ltda. http://www.arsmachina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org -- Howard M. Lewis Ship Creator of Apache Tapestry The source for Tapestry training, mentoring and support. Contact me to learn how I can get you up and productive in Tapestry fast! (971) 678-5210 http://howardlewisship.com -- Andreas Andreou - andy...@apache.org - http://blog.andyhot.gr Tapestry PMC / Tacos developer Open Source / JEE Consulting - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: Tapestry in GAE
Indeed, if you let the app go cold, you will quickly spend a large amount of your GAE free quota on starting up the app (in addition to having a really slow load of the first page). I have a cron task on a separate box that wget-s the whole site every 3 seconds. This ends up eating up about 20% of my free quota every day; however, it keeps GAE from swapping it out and having to cold start the app (which, would have still easily eaten 20% of my free CPU quota anyway). Not to mention, that when the app is not swapped out, there's no real penalty on first load. Not the perfect solution but it works. Regards, Alex K On Mon, Jun 7, 2010 at 2:40 PM, Andreas Andreou andy...@di.uoa.gr wrote: http://www.answercow.com/2010/03/google-app-engine-cold-start-guide-for.htmlis an interesting read on how much startup time is spent on several java libraries at GAE On Mon, Jun 7, 2010 at 19:38, Howard Lewis Ship hls...@gmail.com wrote: That's interesting, that GAE shuts down your instances. There's a bit of Tapestry based on the idea that the application is long running, so it's OK if it takes a moment to start up initially. Under GAE that's not the case ... perhaps Tapestry under GAE should be even a bit lazier about loading and instantiating. When GAE shuts down the instance, is it undeploying the WAR? All told, I think the most significant amount of time spent starting up a T5 app is the initial load of all those classes. I can see these during the Selenium integration tests, where the second test app to start up (all within the same JVM) is much faster because all the framework classes have already been loaded. On Mon, Jun 7, 2010 at 7:01 AM, Thiago H. de Paula Figueiredo thiag...@gmail.com wrote: On Mon, 07 Jun 2010 10:42:52 -0300, Dmitry Gusev dmitry.gu...@gmail.com wrote: This is exactly what I mean, I don't want tapestry to load even once for some requests. GAE shutdown/startup instances very often (one new instance per ~3 minues) and this consumes additional resources. Oops, I forgot this GAE characteristic and what you said makes sense now. :) -- Thiago H. de Paula Figueiredo Independent Java, Apache Tapestry 5 and Hibernate consultant, developer, and instructor Owner, Ars Machina Tecnologia da Informação Ltda. http://www.arsmachina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org -- Howard M. Lewis Ship Creator of Apache Tapestry The source for Tapestry training, mentoring and support. Contact me to learn how I can get you up and productive in Tapestry fast! (971) 678-5210 http://howardlewisship.com -- Andreas Andreou - andy...@apache.org - http://blog.andyhot.gr Tapestry PMC / Tacos developer Open Source / JEE Consulting - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
