rsyncing rawhide -- statistics

[Chris Ricker]

Out of curiosity, I decided to see how effective rsync would be for 
mirroring rawhide.

I already had a full copy of rawhide/i386/RPMS made yesterday morning, so I
made a single large file of the contents of that directory. I then updated
the mirror this evening. 246 megs of RPMs were downloaded during the mirror
update.

I then made a single large file of the updated mirror. I then rsync'ed 
yesterday's file with today's file. The statistics for that were:

Number of files: 1
Number of files transferred: 1
Total file size: 1823997952 bytes
Total transferred file size: 1823997952 bytes
Literal data: 16334848 bytes
Matched data: 1807663104 bytes
File list size: 79
Total bytes written: 667988
Total bytes read: 16778637

So, for a daily update of the rawhide binary RPMs, rsync downloaded 16 megs,
while ftp downloaded 246 megs. That's a very significant savings,
bandwidth-wise!

Of course, this was only one trial, and it may have been anomalous -- for
example, it might be the case that more of the differences between today and
yesterday's rawhide trees were simply repushes of now-signed packages than
is usually the case w/ a daily rawhide update.... I'll benchmark a couple
more days and see what it looks like with repeated samples.

later,
chris