Question about rsync and BIG mirror

[Jamie Lokier]

Shachar Shemesh wrote:
> >Hmm.  My home directory, on my laptop (a mere 60GB disk), does contain
> >millions of files, and it takes about 20 minutes to build the list on
> >a good day.  100Mbps network, but it's I/O bound not network bound.
> >
> >It looks a lot like the number of files is more significant than the
> >amount of data at this scale.
> >  
> >
> In fact, I know of at least one place where they don't use rsync because
> they don't have enough RAM+SWAP to hold the list of files in memory.

That's true when I'm syncing my laptop's home directory (192MB RAM +
256MB swap) to the desktop machine (plenty of RAM).

So I have to split my home directory rsync into two commands, which
copy different parts of it separately.

I suspect the excessive memory usage is due to -H, "preserve hard
links", of which I have many due to mostly-hard-linked Linux kernel
source trees.

That place you mention wouldn't happen to be using the -H option,
would they?

-- Jamie