Don't feel bad - I've now wasted over a day on this! Sorry if I've come across as grumpy in previous emails... but I've wasted over a day on this :-(
Jeff On Thu, Jun 9, 2011 at 4:25 PM, Gal Dolber <gal.dol...@gmail.com> wrote: > Ok, you actually got me to waste 1 hour on benchmarking and I hate to say > that you are right. > The use of reflexion seems not to be heavy enough to make the difference. > Some extra features on slim3 make it slower when you don't make use them, I > almost have a working path to avoid this problem, but even with the patch, > both frameworks give almost the same performance > On Thu, Jun 9, 2011 at 10:15 AM, Dennis Peterson <dennisbpeter...@gmail.com> > wrote: >> >> Haha, excellent. I studied cargo cults a bit in anthropology classes, long >> ago, and never suspected how relevant they would be. >> You would probably enjoy this: >> >> >> http://www.fanfiction.net/s/5782108/1/Harry_Potter_and_the_Methods_of_Rationality >> >> Until Google makes a change, maybe the other frameworks should try the >> same trick? >> >> On Thu, Jun 9, 2011 at 8:31 AM, Jeff Schnitzer <j...@infohazard.org> >> wrote: >>> >>> On Thu, Jun 9, 2011 at 1:32 AM, Gal Dolber <gal.dol...@gmail.com> wrote: >>> > I am not comparing reflexion vs byte-code generation or anything like >>> > that, >>> > apt generates code, is not a runtime technology. >>> > Like or not reflexion is known to be slower than actually writing the >>> > code. >>> >>> This is entirely irrelevant. We've now established that the issue at >>> hand is a strange quirk in the Low-Level API and has nothing to do >>> with reflection. 100% (or close to it) of the performance "gain" of >>> Slim3 is because it calls .size() on a List before iterating it. >>> >>> > Slim3 generates the minimal possible code you need to talk with the low >>> > level api, if the low level bench is faster is just because its not >>> > converting the Entity to the Pojo. >>> >>> You missed the point - in the benchmark, Slim3 was *faster* than the >>> Low-Level API. This clearly indicated something was amiss, and now >>> we've uncovered the actual cause. It turns out to be something quite >>> interesting indeed. >>> >>> This is a classic case of what Feynman called Cargo Cult Science. You >>> all believed that Slim3 should be faster than other APIs because code >>> generation is faster than reflection, so when someone produced an >>> ill-conceived benchmark that seemed to confirm your preconceived >>> notion, you just accepted the entire narrative: "Slim3 is fast >>> because it doesn't use reflection!" This is sloppy thinking (see: >>> Confirmation Bias). >>> >>> If you haven't read this, it's a gem (I make a habit of re-reading it >>> at least once a year): >>> >>> http://www.lhup.edu/~DSIMANEK/cargocul.htm >>> >>> Jeff >>> >>> -- >>> 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 >>> google-appengine-java@googlegroups.com. >>> To unsubscribe from this group, send email to >>> google-appengine-java+unsubscr...@googlegroups.com. >>> 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 >> google-appengine-java@googlegroups.com. >> To unsubscribe from this group, send email to >> google-appengine-java+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/google-appengine-java?hl=en. > > > > -- > Guit: Elegant, beautiful, modular and *production ready* gwt applications. > > http://code.google.com/p/guit/ > > > > > -- > 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 google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > 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 google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
