Smart server usage

[Eugene Wee]

John Arbash Meinel wrote:
> Can you tell me what page you were linked to, so that we can update it to
> include a reference to the HTTP smart server setup?

The page I mentioned is:
http://doc.bazaar-vcs.org/bzr.dev/server.htm


> a) bzr+ssh is usually much faster than sftp://. Mostly noticeable for a large
> 'push' or 'pull'. Because for sftp:// you have to open(), read(), close(),
> which is 3 round trips to get data from 1 file. Even without advanced changes,
> bzr+ssh is a single read(path, bytes) call.
> 
> For very quick functions (bzr update when nothing has changed) it can be
> slightly slower. Because we have to spawn 'bzr' on the remote side, while
> 'sftp' is already running. Dedicated 'bzr://' and 'bzr+http://' would both
> already have a service running, so wouldn't encounter this. (Note, we are
> talking about <500ms here, but when the command only takes 250ms, it is noticeable)

I chanced upon Brett's "Another (unscientific) comparison of Mercurial 
and Bazaar":
http://sayspy.blogspot.com/2007/07/another-unscientific-comparison-of.html

What I find curious is that Brett reports that remote branch, push and 
pull are faster in his tests over sftp than over bzr+ssh. Can the 
process spawning and small "project" size account for the 0.5-0.8 s 
advantage sftp has over bzr+ssh in these rather quick (less than 3 
seconds) test scenarios?

Thanks,
Eugene Wee