package: ucf
version: 3.005
severity: wishlist
When using ucf to manage large numbers of files, I've noticed pauses
while the maintainer script is calling ucf in a loop. I am uncertain as
to what this slowdown is, whether is it ucf startup overhead, or some
other overhead.
For comparison, most conffiles are still managed by dpkg, but I don't
notice slowdowns there.
I'm guessing that this could be allevieated by having a multi-file
dispatch call into ucf; ucf would then loop over each file, figuring out
which state change is needed for each, store this internally, then do a
series of debconf questions based on the data it found. But that's just
a guess.
Attached is the irc log where I discussed this with you.
06:24:08 PM < eigood > Manoj: please do, it's too slow
06:24:17 PM < Manoj > I really did not think there was data that justified
optimization -- and I strongl believe in
not optimizing early
06:24:43 PM < Manoj > eigood: really? You care about how long it takes ucf to
ask you a question?
06:24:55 PM < eigood > Manoj: I care when there are 100+ files to ask
06:25:01 PM < Manoj > how much of that is debconf starting up?
06:25:16 PM < eigood > once for each file? quite a bit
06:25:31 PM < eigood > if you had it as a single program, that gathered all the
data about all the 100+ files, then it
wouldn't be so bad
06:25:42 PM < eigood > you might even do a multi-file version in shell
06:25:46 PM < Manoj > I'll still have to use debconf, and since debconf only
allows asking one question anyway, I
think even a C implementation will have most of the
speed issues
06:25:56 PM < eigood > it certainly does not
06:26:03 PM < eigood > you can ask tons of questions in debconf
06:26:50 PM < Manoj > eigood: well, a shell muti-file question should be tested
06:27:21 PM < eigood > I have no problem asking one question for each file;
generally, the questions wouldn't be asked,
so you'd never even send debconf a "DISPLAY QUESTION"
comman
06:27:22 PM < eigood > +d
06:27:28 PM < Manoj > I always meant to look at how apache module questions
are asked (they have a checkbox per
module, iirc)
06:27:54 PM < weasel > I hate the ca-cert questions
06:27:54 PM < eigood > my issue is the looping in the maintainer script,
calling ucf multiple times
06:28:03 PM < weasel > it's painful to de-select them all
06:28:35 PM < Manoj > eigood: I'll happily add the ability of giving ucf
multiple files, and have it ask one question
using checkboxes, but at this moment I do not know the
debconf calls I'll need to make
06:28:46 PM < eigood > why use checkboxes?
06:28:59 PM < eigood > for each file that needs to have changes
merged/prompted, ask a question
06:29:08 PM < Manoj > well, what if I swant to replace some files, look at
other files, and not replace others?
06:29:18 PM < eigood > look at how dbconfig-common does it, creating a new
question on the fly from a template
06:29:33 PM < eigood > so ask a question for each of those
06:29:42 PM < Manoj > eigood: so how is there a speed increase, if I still
ask N questions?
06:29:57 PM < eigood > because ucf is not called multiple times, and ucf's
startup overhead is reduced
06:30:09 PM < eigood > my problems with the speed are not with the number of
questions asked
06:30:11 PM < Manoj > eigood: Umm.
06:30:30 PM < eigood > in most cases, most questions won't be shown, ever;
config files are not being changed with each
new package release
