this may be _slightly_ off topic, but can i just ask what exactly does putting a hat on the tapestry logo represent? a swirly hat? the penknife with the logo, fair enough... represents tools etc.. but a hat on the logo? WHY IS THERE A HAT ON IT?!?! im finding it hard to work while i dont know the answer to this...
On 3/26/06, Adam Zimowski <[EMAIL PROTECTED]> wrote: > > Just tried Tapestry-Prop and works painlessly with my Tap4 app. Whatta > way to go. And since I already took aggresive approach to keep OGNL > simple, this certainly will eliminate a good half of my OGNL calls. > > Adam > > On 3/26/06, Adam Zimowski <[EMAIL PROTECTED]> wrote: > > How nice. Learning something new everyday. This looks like an obvious > > must-have for any serious Tapestry app. > > > > Thanks Ryan! > > > > On 3/26/06, Ryan Holmes <[EMAIL PROTECTED]> wrote: > > > Don't forget about the Tapestry-Prop library at > > > http://howardlewisship.com/tapestry-javaforge/tapestry-prop/ > > > Combined with the "dot-pruning" technique this will let you eliminate > a > > > lot of OGNL. > > > > > > -Ryan > > > > > > Vincent wrote: > > > > Hi , > > > > > > > > That may explain a lot why the performance of the my application > slow > > > > down a lot recently. > > > > But anyway , is there any plan to improve the performance of OGNL , > > > > since Tapestry 4.0 already released? > > > > > > > > On 3/26/06, Adam Zimowski <[EMAIL PROTECTED]> wrote: > > > > > > > >> Hi Andreas, > > > >> > > > >> FYI, OGNL is one of the biggest bottlencecks in Tapestry. I'm > learning > > > >> about it from performance testing my own app, but I could not say > it > > > >> better than what Patrick explained a while back on this list. His > post > > > >> was regarding Tap 3.0.3, but from my Tap4 tests, the OGNL > performance > > > >> is still very much a case for performance tweaks. In short, try to > > > >> limit your OGNL usage to what's absolutely necessary, and do the > rest > > > >> in plain Java. My app is growing large very quickly, but I'm able > to > > > >> keep OGNL down to simple one-dot expressions. > > > >> > > > >> Perhaps you've seen Patrick's post (it's really well explained), > but > > > >> I'm including it here: > > > >> > ------------------------------------------------------------------------- > > > >> > > > >> From: Patrick Casey <[EMAIL PROTECTED]> Mailed-By: > jakarta.apache.org > > > >> Reply-To: Tapestry users <[email protected]> > > > >> To: Tapestry users <[email protected]> > > > >> Date: Feb 15, 2006 11:38 AM > > > >> Subject: RE: Optimization Questions > > > >> > > > >> The last time I did a serious performance attach on a Tapestry > 3.0.3 > > > >> app, by far the biggest performance bottleneck was the demon OGNL. > Howard > > > >> and I went round and round on that one, but the upshot is that > Howard's > > > >> using OGNL right, and OGNL is actually a decent reflection package > (and > > > >> hence faster than, say, Apache PropUtils), but it's still not > native code. > > > >> > > > >> Given that some page renders can require literally thousands > of OGNL > > > >> calls (I was up at like 1800 distinct evaluations for one page), > its often > > > >> the bottleneck. > > > >> > > > >> I've pasted my OGNL performance hints below. None of it's > rocket > > > >> science, but aggressively following these techniques knocked about > 50% off > > > >> the page render time on my forms, so there's some serious > performance to be > > > >> gained. > > > >> > > > >> --- Pat > > > >> > > > >> Rules to Make OGNL Run Faster: > > > >> > > > >> > > > >> **Dot Pruning: > > > >> > > > >> Reduce the number of "dots" in your calls. For example, lets say > you had a > > > >> call that read: "ognl:foo.bar.dog". That's a three-hopper as far as > OGNL is > > > >> concerned, requiring three times the work of a one hopper like > "ognl:dog". > > > >> You can make the thing run 3X as fast if your go into your page > class and > > > >> create a getter and setter for "dog" e.g. > > > >> > > > >> > > > >> > > > >> Public String getDog() { > > > >> > > > >> Foo foo = getFoo(); > > > >> > > > >> If (foo == null) > > > >> > > > >> Return null; > > > >> > > > >> Bar bar = getBar(); > > > >> > > > >> If (bar == null) > > > >> > > > >> Return null; > > > >> > > > >> Return bar.getDog(); > > > >> > > > >> } > > > >> > > > >> > > > >> > > > >> Public void setDog(String value) { > > > >> > > > >> Foo foo = getFoo(); > > > >> > > > >> If (foo == null) > > > >> > > > >> Return; > > > >> > > > >> Bar bar = getBar(); > > > >> > > > >> If (bar == null) > > > >> > > > >> Return; > > > >> > > > >> Bar.setDog(value); > > > >> > > > >> } > > > >> > > > >> > > > >> > > > >> What we've done is created two java stub classes that do > 2/3 of > > > >> the work for OGNL so it only has to make one "hop" to get at the > methods it > > > >> needs. Net result is it'll run 3X as fast. > > > >> > > > >> > > > >> **Be Static: > > > >> > > > >> > > > >> OGNL isn't smart enough to realize that a reference to a > public > > > >> static final object is, in fact, static. It resolves the whole > thing via > > > >> inspection each time. So if you want to make an expression that > reads, for > > > >> example: > > > >> > > > >> > > > >> > > > >> <span jwcid="@Insert" value="ognl:@[EMAIL PROTECTED]" /> > > > >> > > > >> > > > >> It's faster to do: > > > >> > > > >> > > > >> <span jwcid="@Insert" value="Monday" /> > > > >> > > > >> > > > >> You're kind of Sol if you change "Monday" to "Mon" mind > you, so > > > >> I wouldn't switch over to literals like this until rollout time, > but it does > > > >> make a difference. > > > >> > > > >> > > > >> **Avoid Putting Components Inside Foreach: > > > >> > > > >> There's a lot of OGNL grinding going on behind the scenes to > support a > > > >> foreach, and even more ognl grinding going on to call a component. > So if you > > > >> put the one inside the other, well, CPU cycles burn. So in many > cases: > > > >> > > > >> > > > >> > > > >> <span jwcid="@Foreach" source="ognl:listOfDogs" > values="ognl:currentDog"> > > > >> <span jwcid="@DogDisplay" dog="ognl:currentDog"/> > > > >> <span> > > > >> > > > >> > > > >> Is *dramatically* slower than moving the foreach down into the > DogDisplay > > > >> component e.g. > > > >> > > > >> <span jwcid="@ListOfDogsDisplay" listOfDogs="ognl:listOfDogs" /> > > > >> > > > >> > > > >> And then combing the foreach and the dogdisplay logic inside of one > > > >> component. Otherwise every time the sub component gets called > there's at > > > >> least one ognl set/get pair being executed to push data into the > component > > > >> and pluck it out again. Basically pretend you're working in a > system which > > > >> has *really* inefficient method call overhead and view components > as > > > >> methods. Then optimize to reduce method calls. > > > >> > > > >> **Notes: > > > >> > > > >> If you do your own profiling, one warning I do want to give is that > on > > > >> JProfiler at least, it can "hide" the true culprit in the bowels of > the call > > > >> stack. So if you have an ognl expression that reads > > > >> "ognl:foo.bar.thisMethodTakesForever", it'll show up as a lot of > CPU time > > > >> belonging to ognlGet until you dive into the call stack and get to > > > >> whatever's at the pointy end of the get. Most of the time the > actual get is > > > >> trivial so all the time really is going into OGNL, but sometimes if > you have > > > >> expensive gets (or sets) it can make OGNL look worse than it is. > > > >> > > > >> > --------------------------------------------------------------------- > > > >> To unsubscribe, e-mail: > [EMAIL PROTECTED] > > > >> For additional commands, e-mail: > [EMAIL PROTECTED] > > > >> > > > >> > > > >> > > > > > > --------------------------------------------------------------------- > > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > >
