Re: [Richfaces-exadel] Fwd: [seam-dev] Some profiling of blockingthreads

On Wed, Oct 1, 2008 at 8:12 PM, Dan Allen <dan.j.allen(a)gmail.com&gt; wrote: > Jay, > > This is great work and very interesting to follow. thanks > > > I would like to make a suggestion regarding the tests. Putting the > wiki under test is extremely valuable because it is a complex > application and therefore reflective of our users' applications. > However, it is tricky for others to follow along, because as you > mentioned, it is not trivial to setup. To supplement those tests, > perhaps you can generate a seam-gen application with a test schema > (perhaps stealing from one of the example application) so that we can > compare numbers with yours. What makes a seam-gen application valuable > to test is that it uses the Seam Application Framework, which is a > well known performance bottleneck in Seam because of its excessive use > of getInstance() and joinTransaction(). I think you are correct for the reasons you state and others. The wiki example also does not use EJBs which I suspect a large number of seam apps do. I was planning on looking at the dvdstore next and that uses several technologies (EJB, JBPM, etc...). However I could look at a seam-gen EAR project as well, but I would like to get some other opinions on this. I do not think that I will have enough time to do both. > > It shouldn't take too long to generate the seam-gen application and > reverse engineer the schema. The tedious part is generating a whole > bunch of fake data, but emacs or vi should make quick work of that. Yeah - the fake data is tricky, but there are some tools that can do this for us. > > > -Dan > > On Wed, Oct 1, 2008 at 6:02 PM, Jay Balunas <tech4j(a)gmail.com&gt; wrote: > > The example I was using was the seam wiki example, but that is not a > trivial > > thing to set up. I have not tried the same profiling on the other seam > > examples so I am not 100% sure that they will show the same behavior, > > although I would think that they would. > > > > As for the profiler report - what are you looking for exactly? > Basically > > under load (25 users) I noticed threads blocking on the > > ViewHandlerWrapper.fillChain method. The details are below. > > > > Regards, > > Jay > > > > On Wed, Oct 1, 2008 at 5:56 PM, Alexandr Smirnov <asmirnov(a)exadel.com&gt; > > wrote: > >> > >> Jay, can you send me profiler report or a reference application ? > >> > >> Jay Balunas wrote: > >> > I was able to update and build with RichFaces 3.3.0-SNAPSHOT and saw > >> > your changes. > >> > > >> > The good news is that I no longer see any blocking threads in the > >> > "org.ajax4jsf.application. > >> > AjaxViewHandler" - none at all which is great. > >> > > >> > The bad news is that the performance has not increased in any > >> > meaningful or repeatable way. > >> > > >> > During my profiling I noticed a definite increase in the blocked > >> > threads performing JNDI lookups. My theory is that the > >> > AjaxViewHandler was acting as a gate and effectively slowing down > >> > concurrent requests into Seam proper. These threads now fly straight > >> > through and into Seam processing. They the end up blocked with the > >> > other threads performing the lookups. > >> > > >> > I will continue to look at the lookup issues, and let you all know > >> > what I find. > >> > > >> > -Jay > >> > > >> > > >> > On Tue, Sep 30, 2008 at 2:05 PM, Jay Balunas <jbalunas(a)redhat.com > >> > <mailto:jbalunas@redhat.com>> wrote: > >> > > >> > Excellent - I will build from sources and test the changes. > >> > > >> > I'll post the findings up on seam-dev. > >> > > >> > -Jay > >> > ----- "Nick Belaevski" <nbelaevski(a)exadel.com > >> > <mailto:nbelaevski@exadel.com>> wrote: > >> > > >> > > All, > >> > > > >> > > I've created JIRA issue for this optimization: > >> > > https://jira.jboss.org/jira/browse/RF-4554 and have just fixed > it. > >> > > > >> > > As from now ViewHandlerWrapper#fillChain method is not > >> > synchronized > >> > > anymore. > >> > > > >> > > Best regards, > >> > > Nick Belaevski > >> > > > >> > > > -----Original Message----- > >> > > > From: richfaces-exadel-bounces(a)redhat.com > >> > <mailto:richfaces-exadel-bounces@redhat.com> > >> > [mailto:richfaces-exadel- <mailto:richfaces-exadel-> > >> > > > bounces(a)redhat.com <mailto:bounces@redhat.com>] On Behalf Of > >> > Max Rydahl Andersen > >> > > > Sent: Tuesday, September 30, 2008 10:32 AM > >> > > > To: Jay Balunas; richfaces-exadel(a)redhat.com > >> > <mailto:richfaces-exadel@redhat.com> > >> > > > Subject: Re: [Richfaces-exadel] Fwd: [seam-dev] Some > profiling > >> > of > >> > > > blockingthreads > >> > > > > >> > > > Sergey/Nik ? Any news on this one ? > >> > > > > >> > > > /max > >> > > > > >> > > > > Hi Guys, > >> > > > > > >> > > > > I have been doing some performance testing on seam > >> > applications > >> > > and have > >> > > > > been able to post some of the results. One of the areas > that > >> > I > >> > > have > >> > > > > investigated so far was blocking/waiting threads. > >> > > > > > >> > > > > In my example I am running 25 concurrent users and hitting > the > >> > > seam wiki > >> > > > > example. I am seeing blocked threads waiting on > >> > > > > "org.ajax4jsf.application.AjaxViewHandler". > >> > > > > I have investigated it a bit (see below), and have included > >> > some > >> > > of the > >> > > > > discussions on the seam-dev list. > >> > > > > > >> > > > > I would like to get an opinion of the synchronized > fillChain > >> > > method, and > >> > > > > see > >> > > > > if there is another way to handle this. > >> > > > > > >> > > > > Thoughts? > >> > > > > > >> > > > > Thanks, > >> > > > > Jay > >> > > > > > >> > > > > ---------- Forwarded message ---------- > >> > > > > From: Emmanuel Bernard <emmanuel(a)hibernate.org > >> > <mailto:emmanuel@hibernate.org>> > >> > > > > Date: Thu, Sep 25, 2008 at 10:01 AM > >> > > > > Subject: Re: [seam-dev] Some profiling of blocking threads > >> > > > > To: Jay Balunas <tech4j(a)gmail.com <mailto:tech4j@gmail.com > >> > >> > > > > Cc: Pete Muir <pmuir(a)redhat.com <mailto:pmuir@redhat.com > >>, > >> > &quot;seam-dev(a)lists.jboss.org <mailto:seam-dev@lists.jboss.org>" < > >> > > > > seam-dev(a)lists.jboss.org <mailto:seam-dev@lists.jboss.org > >> > >> > > > > > >> > > > > > >> > > > > > >> > > > > On Sep 25, 2008, at 09:17, Jay Balunas wrote: > >> > > > > > >> > > > > org.ajax4jsf.application.AjaxViewHandler > >> > > > >> -------------------------------------------- > >> > > > >> - This was not a large % of the blocked threads but > caught > >> > my > >> > > eye as a > >> > > > >> potential trouble spot because it seemed directly related > to > >> > > ajax > >> > > > calls. > >> > > > >> - This was easier to track down and the root cause is in > the > >> > > > >> org.ajax4jsf.application.ViewHandlerWrapper class. > >> > > > >> - see > >> > > > >> > >> > > > > >> > > > >> > > >> > > http://anonsvn.jboss.org/repos/richfaces/trunk/framework/api/src/main/java > >> > > > /org/ajax4jsf/application/ViewHandlerWrapper.java > >> > > > >> - The problem is all the calls to "fillChain" which is a > >> > > synchronized > >> > > > >> method in the class. > >> > > > >> - We need to find out how often the "_initialized" field > is > >> > > false - is > >> > > > >> this once a request, once for each component, etc... > >> > > > >> - it appears to be called many times - I will look > further > >> > into > >> > > this. > >> > > > >> > >> > > > >> > >> > > > > I will raise this the richfaces dev guys, and see what can > be > >> > > done. > >> > > > > > >> > > > > > >> > > > > Using the double check lock pattern with a volatile should > >> > make > >> > > things > >> > > > > better. It has to be done right though :) > >> > > > > > >> > > > > > >> > > > > > >> > > > > >> > > > > >> > > > > >> > > > -- > >> > > > /max > >> > > > > >> > > > _______________________________________________ > >> > > > Richfaces-exadel mailing list > >> > > > Richfaces-exadel(a)redhat.com <mailto: > Richfaces-exadel(a)redhat.com&gt; > >> > > > https://www.redhat.com/mailman/listinfo/richfaces-exadel > >> > > > >> > > _______________________________________________ > >> > > Richfaces-exadel mailing list > >> > > Richfaces-exadel(a)redhat.com <mailto: > Richfaces-exadel(a)redhat.com&gt; > >> > > https://www.redhat.com/mailman/listinfo/richfaces-exadel > >> > > >> > > >> > > >> > > >> > -- > >> > blog: http://in.relation.to/Bloggers/Jay > >> > > ------------------------------------------------------------------------ > >> > > >> > _______________________________________________ > >> > Richfaces-exadel mailing list > >> > Richfaces-exadel(a)redhat.com > >> > https://www.redhat.com/mailman/listinfo/richfaces-exadel > >> > > > > > > > > -- > > blog: http://in.relation.to/Bloggers/Jay > > > > _______________________________________________ > > Richfaces-exadel mailing list > > Richfaces-exadel(a)redhat.com > > https://www.redhat.com/mailman/listinfo/richfaces-exadel > > > > > > -- > Dan Allen > Software consultant | Author of Seam in Action > > http://mojavelinux.com > http://mojavelinux.com/seaminaction > > NOTE: While I make a strong effort to keep up with my email on a daily > basis, personal or other work matters can sometimes keep me away > from my email. If you contact me, but don't hear back for more than a > week, > it is very likely that I am excessively backlogged or the message was > caught in the spam filters. Please don't hesitate to resend a message if > you feel that it did not reach my attention. > -- blog: http://in.relation.to/Bloggers/Jay