Re: profiling, what takes so long?

[Brendan Heading]

Johan Bezem writes: 

> I had this situation about 2 years ago, using Cygwin on windows, and CC 
> dynamic views.
> Since both were mandatory parts of the project, I had to find sth else.
> FWIW: Make sure that intermediate files, temp directories and such 
> definitely are created on a local drive.
> If you treat a dynamic view as read-only, the impact is far smaller, so 
> split the source and object trees. And if you can, use snapshot views.

Dynamic views (particularly if read/write) are the whole point of using 
Clearcase in the first place, they are what make it powerful. However in 
exchange for that power you have terrible performance. Each stat() requires 
a lookup, over a network link, on the CC server. Snapshot views are just 
like souped-up CVS. 

As others have said, tmp directories (or gcc -pipe) located locally are an 
important way to improve performance. However, if you are serious about 
using Clearcase then you can use Clearmake. It is mostly compatible with the 
core GNU Make syntax, but it works around the performance problems by 
avoiding builds in the first place - if you or someone else has built a file 
before using the same source elements then it avoids rebuilding it. It's 
kind of like a very clever "ccache". 

Brendan