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 On Mon, 2007-07-30 at 17:32 -0400, Jonathan Bober wrote: > Short answer: This has occurred to me, and I don't think that it is the > problem. > > I'll try to document this carefully and give a more detailed answer > later. > > On Mon, 2007-07-30 at 14:25 -0700, William Stein wrote: > > On 7/30/07, David Harvey <[EMAIL PROTECTED]> wrote: > > > Hi, I haven't been following closely, but I wonder if it's a static vs > > > shared thing. But usually that shouldn't account for such a large > > > difference, so that's probably not the issue. > > > > Do you build and link in the dynamic version of GMP? There > > might be a speed difference between static and dynamic. > > > > William > > > > > > > > > > > > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
