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 <tapestry-user@jakarta.apache.org> > > >> To: Tapestry users <tapestry-user@jakarta.apache.org> > > >> 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]
