Re: svn commit: r190514 - head/sys/conf

On Friday 14 August 2009 11:33:47 am Tim Kientzle wrote:
> John Baldwin wrote:
> > On Thursday 13 August 2009 2:57:10 pm Doug Barton wrote:
> >> Bjoern A. Zeeb wrote:
> >>> Author: bz
> >>> Date: Sat Mar 28 23:17:18 2009
> >>> New Revision: 190514
> >>> URL: http://svn.freebsd.org/changeset/base/190514
> >>>
> >>> Log:
> >>>   For kernel builds reduce the impact of svnversion, just scanning
> >>>   src/sys and not the entire src/ tree.
> 
> Performance here I think is a red herring.  This is
> really about correctness:  The SVN revision of usr.bin/ls
> simply isn't relevant for the kernel build.

Very true.

> >> Also, what problem are we really trying to solve here? With a
> >> populated cache it takes on average 5 seconds to run all of src, and
> >> just under 1 to do only sys. Is 4 seconds really that important to
> >> save? With a dry cache I'm sure it takes a little longer, but has
> >> anyone actually measured this?
> 
> I just measured over 30 seconds for svnversion against /usr/src and
> around 6 for /usr/src/sys (both with cold cache).
> 
> > It takes far longer than 5 seconds here against a local SVN repo over NFS.
> 
> The repo has nothing to do with it.  svnversion doesn't
> talk to the repo.  It only examines the working copy.

Ah, true.  My checkouts are also over NFS though rather than local disk which 
may explain it still.

-- 
John Baldwin