On Feb 1, 2012, at 9:34 AM, Rémi Forax wrote: > On 02/01/2012 01:52 AM, Mark Roos wrote: >> I just loaded about 250K lines of Smalltalk code into my jvm >> implementation so now I can start >> some real benchmarks using our application. All of this was done on a >> Mac. >> >> My first try was a object load which takes about 20 files and creates >> a pretty complex object set. This >> takes 100 seconds in ST and using the initial jdk7 release I also get >> 100 seconds. Not bad. But >> I see that one of the major slowdowns is in my use of boxed integers >> vs STs use of Fixnums. So >> I did some more detailed experiments. >> >> Using this code snippet which creates and drops about 2 million >> Integers which ST does in about 10ms. >> >> | bytes pos sum | >> bytes := ByteArray new:1000000. >> sum := 0. >> pos := 1. >> [pos <= 1000000] whileTrue:[ >> sum := bytes at:pos. >> pos := pos + 1]. >> ^sum >> >> For the initial JDK7 I get 400ms, moving to jdk8 b20 it drops to >> 117ms ( very nice). >> I then converted some constructor lookups to statics to get to 66ms. >> Then the obvious move to make an integer cache for which I used the >> jTalk range of -2000 to 4000 gave 30ms >> And finally ( to handle the index integer) I created a MutableInteger >> which dropped me to 5ms. >> >> So 2X better than the ST I started with. >> >> But then I upgraded to jsk8b23 and now the best I see is 16ms. It >> also seems like the jit sometimes >> compiles and sometimes not even using the same startup sequence. >> Bleeding edge I would guess. >> >> But for the final test I used jdk7u4 and my load is 73 seconds. Not >> as good as the best jdk8b20 ( 60 seconds) >> but faster than native Smalltalk > > Hi Mark, I believe tiered compilation was enable by default between > jdk8b20 and jdk8b23. > I have seen some weird compilation pattern too but no time to really > investigate.
I was thinking about the same. Try -XX:-TieredCompilation to know for sure. -- Chris > >> >> looking good >> mark > > Rémi > > _______________________________________________ > mlvm-dev mailing list > mlvm-dev@openjdk.java.net > http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev _______________________________________________ mlvm-dev mailing list mlvm-dev@openjdk.java.net http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev
