cvup mirrors and exact CVS dates

[Erik Cederstrand]

Hi!

I'm chugging along with the performance tracker project[1]. I have a 
script constantly building jails using the newest CURRENT sources, and 
since reproduceability is one of the goals, I have some questions 
regarding cvsup mirrors and CVS in general (hope it's OK on this list):

1) To identify the jails, I name them after the CVS date I put in the 
cvsup file. Now, if the date is now() (converted to UTC), can I be sure 
that any given mirror (retrieved by fastest_cvsup) has the same set of 
files? Or will some mirrors be behind and happily give me sources that 
are older than what the main CVS server would report for that specific 
CVS date?

2) On the same note, is there any way to uniquely identify a global 
revision of the FreeBSD source tree, comparable to revisions in 
Subversion? From what I understand, there is no way to know if e.g. CVS 
dates 2007.10.25.13.45.00 and 2007.10.25.13.46.00 represent the same 
source code, except updating to both dates and seeing if any files change.

Please Cc: me, I'm not on the list.

Thanks!
Erik Cederstrand

[1] http://wiki.freebsd.org/PerformanceTracker