rsync for PDAs?

[Martin Pool]

On  6 Aug 2002, Donovan Baarda <abo at minkirri.apana.org.au> wrote:
> On Mon, Aug 05, 2002 at 12:13:49PM -0700, Cliff L. Biffle wrote:
> > I've been working for the past few months with open-source solutions for 
> > syncing Palm PDAs (Coldsync, mostly).  I've been becoming increasingly 
> > annoyed with Palm's Desktop Link Protocol and the sync mechanism, and am 
> > considering replacing it with a third-party application for the Palm.  Since 
> > I've had good luck with rsync in the past, its seemed an obvious choice.
> > 
> > I've read over the technical documentation and the algorithm looks like it 
> > could be implemented on a 'small' system.  (In this case small is roughly 
> > 20mhz+, with very little RAM available on top of that used for storing 
> > files.)  However, theory rarely reflects reality.  My question is for anyone 
> > who has experience implementing rsync: how processor/RAM intensive is it 
> > really?  Is this a pipe dream for resource reasons?
> > 
> > (Now, I'd probably be using a slightly modified rsync, because files in PalmOS 
> > aren't flat files, but rather record databases.  However, that'd just mean 
> > the software should be record-aware, but probably won't require a lot of 
> > modification.)

I too would strongly recommend that you use librsync rather than
rsync.

It's not the resource problems that will get you but e.g. the
hardcoding of a fork() model into rsync, and just the knottiness of
the code.  I'm not saying it would be impossible, but librsync would
be easier.

Presumably you could make some headway by just sending checksums of
records that are possibly changed but may not be.

-- 
Martin