[PATCH 3/3] Open files only once

[Ed W]

Did this message reach the mailing list also?  I noticed messages only 
CC'd to the list don't seem to go there, but it could be something else 
like my poor maildrop rules?

> It depends on the machine. Some have rsync 2, others have rsync 3. rsync
> doesn't consume as much memory because it's written in C (read as: no
> additional language memory overhead). I'm configuring rsnapshot[1] using
> slack[2] to do the work for me.
>   

rsync3 has an incremental mode which allows it to cut memory usage quite 
considerably.  It relies on a few things coming into alignment though so 
it may not be operating for you anyway? (see the man page).

Have you tried snapback2 versus rsnapshot?  I like the former because 
you just setup one cronjob and it rotates everything automatically.  No 
need for multiple manual cronjobs to rotate things (which seems possibly 
error prone if the machine is rebooted at the wrong time)  However, I 
haven't played much with rsnapshot to see if there are other features 
which make it a winner.

I'm not sure the difference in memory consumption is entirely down to 
language though - I think rsync has simply been written to run extremely 
tightly and a lot of thought given to the datastructures (I say this 
without having looked at the code).  I would think it possible for 
brackup to get within say a factor of 2 of the consumption of rsync, and 
perhaps to get close to equalling it with some thought to algorithms for 
large amounts of files? (buffer to disk?)


Thanks to all who develop brackup

Ed W