[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

RE: Re: A question on version numbers

From: Charles Doucette <charles.doucette_at_synxis.com>
Date: 2004-09-24 18:59:25 CEST

Why aren't revision numbers unsigned internally?
Can you have a negative version number?

Chuck

-----Original Message-----
From: kfogel@newton.ch.collab.net [mailto:kfogel@newton.ch.collab.net]
On Behalf Of kfogel@collab.net
Sent: Friday, September 24, 2004 11:01 AM
To: Lee Butcher
Cc: users@subversion.tigris.org
Subject: Re: A question on version numbers

Lee Butcher <lee_butcher@yahoo.co.uk> writes:
> Take this as the situation:
> 30 engineers, working on 200 files. Each engineer commits one file
> per day so there will be 30 commits in 1 day. That means the global
> version number will go from 0-30 in one day.
> The average project is 8 weeks which is 40 working days. At the end of

> the project the global version numner will be up to 1200.
> Have I understood the versioning system of Subversion correctly? Each
> commit increments the global version by 1?
> How high can this version number go?

You have understood global revisions correctly.

Internally, revision numbers are a typedef to 'long int'. That means
means in the very *worst* case you're safe for about 4 years at the
current rate. (C guarantees only 16 bits for 'long int', and in our
case it's a signed long int, so it's really 15 bits == 32768 maximum
revisions.)

However, the worst case is unrealistic. Modern C systems usually just
set 'long int' to the natural width of the processor, and I doubt
anyone's running Subversion on anything less than a 32-bit processor
today. That's a maximum revision of 2147483648, which would take you...
265121 years to use up?

So I think you're okay.

-Karl

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
For additional commands, e-mail: users-help@subversion.tigris.org

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
For additional commands, e-mail: users-help@subversion.tigris.org
Received on Fri Sep 24 19:01:28 2004

This is an archived mail posted to the Subversion Users mailing list.

This site is subject to the Apache Privacy Policy and the Apache Public Forum Archive Policy.