Re: Abolishing ChangeLog files

[Dmitry Gutov <dgutov@yandex.ru>]

On 28.03.2013 21:34, Eli Zaretskii wrote:
>> From: Dmitry Gutov <dgutov@yandex.ru>
>> Date: Thu, 28 Mar 2013 21:20:44 +0400
>> Cc: Stefan Monnier <monnier@iro.umontreal.ca>, emacs-devel@gnu.org
>>
>>>    D:\gnu\bzr\emacs\trunk>timep bzr log --line -l5000 > nul
>>>
>>>    real    00h00m00.921s
>>>    user    00h00m00.875s
>>>    sys     00h00m00.062s
>>>
>>>    $ time git log --oneline -n5000 > /dev/null
>>>
>>>    real    0m0.218s
>>>    user    0m0.015s
>>>    sys     0m0.015s
>>>
>>> I hope you at least won't claim that 900 msec is "much more quickly"
>>> than 200 msec.  (Not that anyone should ever need to look at 5000
>>> revisions.)
>>
>> Your conclusion here seems to be the reverse of what the command output
>> shows (900ms for Bazaar and 200ms for Git).
>
> It was a typo.  See my followup message.

I saw it after I sent the reply.

To answer your question, then, yes, 4.5 times faster indeed is "much 
more quickly". The difference here is not critical, but nice to have.

>> In my experience, Bzr is especially slow when showing log for a subtree
>> or a specific file.
>
> I could ask you to show numbers (because I have no such experience),
> but I won't.  No one in this thread wants any serious discussion,
> anyway.

I would send you the numbers if you pointed me at the mingw port of 
'time' you're apparently using. But here's an example command:

   git log lisp\progmodes\ruby-mode.el | less

It takes about 300ms on the first run and is instantaneous after that.

If I call the respective command in a Bazaar repository, it takes about 
4 seconds on every run, Bazaar doesn't seem to do any caching here. Note 
that I'm using version 2.5.1, it could be better in the latest beta.

Anyway, the most important speedup I expect to see is the time it takes 
to do "git pull" vs "bzr update". I haven't done any real testing there 
yet, but the latter command takes entirely too long. Of course, most of 
that is due to the server being overloaded.

Speaking of removing changelogs, I think the foremost challenge is 
keeping the format. We don't have anything similar to 
`add-change-log-entry' for the log-edit buffer, and I'm not sure how 
that would even work.