Slow VC++ builds from Linux fileserver

[David Collier-Brown]

Jim Hague wrote:
> 
> >As a table:
> >       Server          Client          Time
> >       ------          ------          ----
> >       UltraSparc      NT4             33
> >       Linux           NT4             165
> >       NT4             NT4             -
> >       UltraSparc      win95           54
> >       Linux           win95           54
> >       NT4             win95           64
> 
> Thanks for the suggestions. Unfortunately I haven't managed to make any
> progress, and won't be able to now - I'm leaving this job today.
> 
> As suggested, I've tried switching oplocks/share/locking/etc on and off,
> with no major differences. I have discovered that it's related to the
> precompiled header handling. Without precompiled headers, W95 and NT4
> clients proceed at the same speed.
> 
> Looking at a log dump, it would appear what is going on is that NT4 is
> getting some sort of status information that convinces it that the
> precompiled header file is invalid; it reads it happily, then suddenly
> truncates it and rebuilds it.  This would appear to be the cause of the
> slow performance rather than a particularly slow transaction. If I had the
> time and resources, the next thing I'd do is to take a packet log and
> compare the built from Samba and a NT4 server and see if I could spot a
> point at which the transactions diverge.

	Aha!
	Although I can't speak to the immediate problem,
	I can suggest an underlying strategy: look and
	see if the headers include each other in large
	and foolish fashion.

	A colleague just reduced an 8-hour build to a 2-hour build
	by discovering a deep tree of header-includes-header
	that the end developers didn't realize they were using.
	Probably fixed some ``redefined'' bugs too (:-))

--dave (who just looked at his current project and
	found: guess what! recursive include trees) c-b
-- 
David Collier-Brown,  | Cherish your enemies.  They're harder to
185 Ellerslie Ave.,   | come by than friends and more motivated.
Willowdale, Ontario   | davecb at canada.sun.com, hobbes.ss.org
N2M 1Y3. 416-223-8968 | http://java.science.yorku.ca/~davecb