On Monday, 25 June 2012 12:29:45 UTC+1, Dima Pasechnik wrote: > > > > On Monday, 25 June 2012 10:51:12 UTC+1, Volker Braun wrote: >> >> Whether you are using hdd or ssd for storage only matters for the first >> startup. I have Sage installed on a hdd on my desktop and starting from a >> cold cache takes about 11s, and any subsequent start about 700ms. The >> 100.000 stupid filesystem calls really only mean that the directory >> structure needs to be read once into cache, and from then on we are just >> using the fs cache as a in-memory database. >> >> The only caveat to this is that you might have your filesystem mounted >> with atime (save read-access time to files). Nobody in his right mind does >> that anymore under Linux, pretty much everybody has now switched to >> relatime (save read-access time only if it is older than file creation >> time) or noatime. >> > > OSX definitely uses atime, as one can see "Last opened" time/date for each > file on the system. > Here is a way to turn it off, apparently: > http://dubdubdub.co.uk/2010/01/disabling-atime-updates-on-macos-x > (I didn't try it myself) >
I just tried this, and didn't see any difference. That's what my mount says: nash:~ dima$ mount /dev/disk0s2 on / (hfs, local, journaled, noatime) devfs on /dev (devfs, local, nobrowse) map -hosts on /net (autofs, nosuid, automounted, nobrowse) map auto_home on /home (autofs, automounted, nobrowse) Could it be journalling that slows things down that much? This is on OSX10.6.8 macbook air (Core 2): nash:~ dima$ time /usr/local/src/sage/sage-5.1.beta2/sage < /dev/null ---------------------------------------------------------------------- | Sage Version 5.1.beta2, Release Date: 2012-06-03 | | Type "notebook()" for the browser-based notebook interface. | | Type "help()" for help. | ---------------------------------------------------------------------- ********************************************************************** * * * Warning: this is a prerelease version, and it may be unstable. * * * ********************************************************************** sage: Exiting Sage (CPU time 0m0.04s, Wall time 0m0.04s). real 0m2.208s user 0m1.408s sys 0m0.852s > > >> Mostly because git can become horribly slow with atime. Though I think >> OSX has not caught up to that yet, though I don't have a Mac to test it. >> You can try >> >> mount -vuw -o noatime / >> >> and see if it makes a difference for you. >> >> [vbraun@volker-desktop ~]$ time sage < /dev/null >> ---------------------------------------------------------------------- >> | Sage Version 5.1.beta5, Release Date: 2012-06-19 | >> | Type "notebook()" for the browser-based notebook interface. | >> | Type "help()" for help. | >> ---------------------------------------------------------------------- >> ********************************************************************** >> * * >> * Warning: this is a prerelease version, and it may be unstable. * >> * * >> ********************************************************************** >> sage: >> Exiting Sage (CPU time 0m0.01s, Wall time 0m0.01s). >> >> real 0m0.659s >> user 0m0.541s >> sys 0m0.124s >> >> >> >> On Monday, June 25, 2012 6:00:47 AM UTC+1, William wrote: >>> >>> I think OS X is by default slower than Linux at the (like 100,000 >>> stupid) filesystem calls that Sage does every time it starts up. >>> With my OS X 10.7.4 laptop, which has a very fast SSD, I get the >>> following repeatedly: >> >> >>> blastoff:~ wstein$ time sage < /dev/null >>> ---------------------------------------------------------------------- >>> | Sage Version 5.0, Release Date: 2012-05-14 | >>> | Type notebook() for the GUI, and license() for information. | >>> ---------------------------------------------------------------------- >>> sage: >>> Exiting Sage (CPU time 0m0.01s, Wall time 0m0.01s). >>> real 0m1.526s >>> user 0m1.064s >>> sys 0m0.504s >>> >>> On exactly the same laptop using a Linux Virtualbox virtual machine I >>> get this repeatedly: >>> >>> sagews@sagewsworker:~$ time sage </dev/null >>> ---------------------------------------------------------------------- >>> | Sage Version 5.0.1, Release Date: 2012-06-10 | >>> | Type notebook() for the GUI, and license() for information. | >>> ---------------------------------------------------------------------- >>> sage: >>> Exiting Sage (CPU time 0m0.02s, Wall time 0m0.02s). >>> >>> real 0m0.992s >>> user 0m0.784s >>> sys 0m0.212s >>> >>> >>> >>> I don't know if there are filesystem or OS parameters in OS X that one >>> could change that would speed things up. >>> >>> William >>> >> -- 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
