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

Re: BDB log file factoids (prbly part of why they are so big)

From: Greg Hudson <ghudson_at_MIT.EDU>
Date: 2003-04-06 00:58:52 CEST

On Sat, 2003-04-05 at 12:46, Tom Lord wrote:
> The amount of application data that can change will (if I understand
> svn right) sometimes be quite substantial (as when a file is
> redeltified). In a case such as that, committing a small delta to the
> database can expand the log with complete before and after copies of
> the entire history of the redeltafied file.

If there are N previous revisions of a file, then at most lg(N) deltas
are rewritten by the redeltification process (and the average number of
rewritten deltas is a constant less than 2). But you're right in your
subsequent message that we're probably writing out the file contents
twice to the logfile and once to the db, which is pretty wasteful in
disk bandwidth and short-term space use.

To unsubscribe, e-mail: dev-unsubscribe@subversion.tigris.org
For additional commands, e-mail: dev-help@subversion.tigris.org
Received on Sun Apr 6 00:59:39 2003

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

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