Re: New dselect method
On 30 Jan 1997, Juergen Menden wrote:
> Andy Mortimer (andy.mortimer@poboxes.com) wrote:
> :
> : o Does NOT use dpkg -iGROEB, but instead parses the status and
> : available files. Speedups can be dramatic.
>
> and slowdown can even be very dramatic. please make sure that
> this portion is _really_ effective (flex/bison, compiled).
>
> dpkg-ftp currently uses a similar aproach and on an m68k
> (somewhat like an 40MHz i486) it is unbelievable slow!
> it takes more than a cuple of minutes before download
> is started... :-(
Some timings:
standard dselect `nfs' method: 7 minutes
dpkg-ftp method: 50 seconds
dpkg-mountable method: 15 seconds
Admittedly all these timings are for a system with no new packages to
install, which is going to bias them in favour of the faster methods.
Initial testing, however, showed a 3-4 times speed improvement in the
parsing section (about 11 seconds for dpkg-mountable versus 35-40 for
dpkg-ftp). This is on a 486DX4/100.
This speedup in parsing is because dpkg-ftp reads the entire packages
file into memory, which dpkg-mountable doesn't need to do. They are both
written in Perl; admittedly a bison/flex parser might speed things up
even more, but I don't know it!
&E
--
Andy Mortimer, andy.mortimer@poboxes.com
http://www.netforward.com/poboxes/?andy.mortimer
Finger asm21@asm21.emma.cam.ac.uk for PGP public key
--
Would you pay life's pleasures to see me?
Does it hurt, for I want you to remain?
--
TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to
debian-devel-REQUEST@lists.debian.org . Trouble? e-mail to Bruce@Pixar.com
Reply to: