hmmmm okay there's a few pedantic things I'd like to check.
First, in some of the samples below you had the include directory
wrong, e.g.
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3
> -L/home/bober/sage-2.7.1/sage-2.7.1/local/lib
> -I/home/bober/sage-2.7.1/sage-2.7.1/local/lib -lmpfr -lgmp
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 150003 2007-07-30 20:14 a.out
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m46.675s
> user 0m46.515s
> sys 0m0.116s
Just to check nothing funny is coming from the gmp.h files maybe should
just run those ones again.
Second: you're using various standard C++ library things, but in sage's
setup.py script, the entry for sage.combinat.partitions doesn't mention
"stdc++", whereas there are plenty of others that do. I don't
understand why those other ones have "stdc++" whereas partitions gets
away without it. Seems a bit fishy to me, but probably not the bug
we're looking for.
Third: can we get the program to printf("%s", gmp_version) to check the
GMP version that's getting linked in.
Fourth: is there some way to tell exactly which shared library is being
used when booting up the shared versions? I'd like to check that it's
really using the library we think it is. I used to know how to do this.
There's some unix command which will print out the libraries that are
loaded when the program starts, but I can't remember how to do it.
Fifth: The sage install log mentions a few patches, namely the
"gmp-4.2.1-core2-port" patch, the "gmp_add_nc.patch" patch, and
"mpn_amd64.42" patch. I assume sage patches these in before building
GMP, and that your build doesn't include these patches. Try either (a)
building sage without those patches, or (b) apply them to your separate
GMP build, and see whether that makes any difference.
Actually the last one seems most promising, maybe try that first.
david
On Jul 30, 2007, at 5:36 PM, Jonathan Bober wrote:
> Here are some examples of timings with different compilation options.
> (I'm using 3*10^8) here because it takes long enough to see the
> difference, but short enough to conveniently run lots of tests.
>
> After running hg_sage.pull() to get the newest version, of the code, I
> get:
>
> sage: time a = number_of_partitions(300000000, algorithm='bober')
> CPU times: user 46.81 s, sys: 0.04 s, total: 46.85 s
> Wall time: 47.19
>
> Now I copy the code somewhere else and compile it, linking it to the
> Ubuntu-installed libraries:
>
> [EMAIL PROTECTED]:~/sage-2.7.1/sage-2.7.1/devel/sage-bober/sage/combinat$ cp
> partitions_c.cc ~/temp/
> [EMAIL PROTECTED]:~/sage-2.7.1/sage-2.7.1/devel/sage-bober/sage/combinat$ cd
> ~/temp
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3 -lgmp -lmpfr
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 27529 2007-07-30 20:01 a.out <-- Look at size
> of file to make sure we aren't linking statically
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m36.171s
> user 0m36.110s
> sys 0m0.016s
>
> Now do the same thing, but link statically:
>
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3 -lmpfr -lgmp -static
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 1452497 2007-07-30 20:08 a.out <-- Much
> bigger binary
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m34.240s
> user 0m34.146s
> sys 0m0.020s
>
> Now we build with the libraries included in sage. (Note that
> sage does not build a shared library version of mprf, so
> this binary is bigger than first we build.) The time this
> takes to run is comparable to the time it took to run from
> within sage, so we know the overhead isn't from sage.
>
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3
> -L/home/bober/sage-2.7.1/sage-2.7.1/local/lib
> -I/home/bober/sage-2.7.1/sage-2.7.1/local/lib -lmpfr -lgmp
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 150003 2007-07-30 20:14 a.out
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m46.675s
> user 0m46.515s
> sys 0m0.116s
>
> Now build a static version of the library. (It looks like sage
> only builds a shared library version of gmp, so I'm not sure if
> this really works the way it is supposed to, but it runs at a
> similar speed.)
>
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3
> -L/home/bober/sage-2.7.1/sage-2.7.1/local/lib
> -I/home/bober/sage-2.7.1/sage-2.7.1/local/lib -lmpfr -lgmp -static
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 1479519 2007-07-30 20:19 a.out
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m43.592s
> user 0m43.443s
> sys 0m0.012s
>
> Now we build using the gmp 4.2.1 and mfpr 2.2.1 that I just built.
>
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3 -L/home/bober/local/lib/
> -I/home/bober/local/include/ -lmpfr -lgmp
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 114849 2007-07-30 20:26 a.out
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m35.630s
> user 0m35.206s
> sys 0m0.060s
>
> And one more time, linking statically to those libraries
>
> [EMAIL PROTECTED]:~/temp$ g++ partitions_c.cc -O3 -L/home/bober/local/lib/
> -I/home/bober/local/include/ -lmpfr -lgmp -static
> [EMAIL PROTECTED]:~/temp$ ls -l a.out
> -rwxr-xr-x 1 bober bober 1401979 2007-07-30 20:29 a.out
> [EMAIL PROTECTED]:~/temp$ time ./a.out 300000000
> [...]
> real 0m33.924s
> user 0m33.354s
> sys 0m0.052s
>
>
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