For comparision, I'm using kvm to virtualize our sage notebook server. Here's the timings for your scripts:
A) the real hardware 0.196608066559 1 0.191864967346 -500000 B) the kvm instance 0.219820976257 (11.8% slowdown) 1 0.213951826096 (11.5% slowdown) -500000 Gonzalo On Fri, Oct 23, 2009 at 7:38 PM, Ondrej Certik <ond...@certik.cz> wrote: > > Hi, > > I tried the latest Sage virtualbox appliance, it works on ubuntu 9.04, 64bit. > > I then used this simple script (in a terminal) to get some idea how fast it > is: > > from timeit import default_timer as clock > def test1(): > a = 0 > t = clock() > for i in range(1, 10**6): > a += 1/i**2 > t = clock() - t > print t > return a > > print test1() > > > and then test it on my system: > > $ python2.5 t.py > 0.198249101639 > 1 > > > and in the virtualbox: > > # python a.py > 2.60369110107 > > E.g. it's about 13x slower. > > For comparison, in the virtual machine at linode.com, I get: > > $ python t.py > 0.25862288475 > 1 > > Then it occured to me that maybe just floating point stuff is slow, or > maybe i**2 is too big. So I modified the script: > > > from timeit import default_timer as clock > def test1(): > a = 0 > t = clock() > for i in range(1, 10**6): > if i % 2 == 0: > a += i > else: > a -= i > t = clock() - t > print t > return a > > print test1() > > which runs on ubuntu: > > $ python2.5 t.py > 0.212127923965 > -500000 > > > and in the virtualbox on the same machine: > > # python a.py > 0.267327070236 > -500000 > > > Which is only about 1.2x slower. So apparently virtualbox is very fast > for some things. > > Ondrej > > > > --~--~---------~--~----~------------~-------~--~----~ To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
