On Sep 30, 7:38 am, Gary Robinson <gary...@me.com> wrote: > The chart > athttp://shootout.alioth.debian.org/u32q/benchmark.php?test=all〈=ja...is very > interesting to me because it shows CPython using much less memory than Java > for most tests. > > I'd be interested in knowing whether anybody can share info about how > representative those test results are. For instance, suppose we're talking > about a huge dictionary that maps integers to lists of integers (something I > use in my code). Would something like that really take up much more memory in > Java (using the closest equivalent Java data structures) than in CPython? I > find it hard to believe that that would be the case, but I'm quite curious. > > (I could test the particular case I mention, but I'm wondering if someone has > some fundamental knowledge that would lead to a basic understanding.) >
1) That URL is approximate averages rather than the straight Java measurements. 2) Unless the programs are using *a lot* of memory you're just seeing default JVM memory use. 3) More of the Java programs may have been re-written to use quad core, which may use extra buffering. So look for tasks that use a lot of memory and watch for time/space tradeoffs - 2.1 Java 6 -server #2 29.32 259,868 62 Python #6 14 min 674,316 167 Python #2 38 min 221,236 http://shootout.alioth.debian.org/u32/benchmark.php?test=binarytrees&lang=all 2.8 Java 6 -server #2 46.87 363,488 34 Python 9 min 439,196 http://shootout.alioth.debian.org/u32/benchmark.php?test=knucleotide&lang=all 2.5 Java 6 -server #4 2.87 473,324 6.5 Python #3 7.67 543,908 http://shootout.alioth.debian.org/u32/benchmark.php?test=revcomp&lang=all -- http://mail.python.org/mailman/listinfo/python-list
