[ALUG] Why is rsync forking copies of itself?

[Phil Ashby]

On Mon, 2007-12-10 at 12:39 +0000, Chris G wrote:
> I'm running some backups using rsync, it seems to be spawning multiple
> copies of itself:-
> 
>     root      4426  4424  1 11:24 ?        00:01:14 rsync -rqt --size-only /home /freecom/backup
>     root      4427  4426  0 11:24 ?        00:00:01 rsync -rqt --size-only /home /freecom/backup
>     root      4429  4427  4 11:24 ?        00:02:53 rsync -rqt --size-only /home /freecom/backup
> 
> Why is it doing this?  .... and *should* it be doing this as all three
> copies of rsync appear to be doing exactly the same thing.

Most likely this is rsync creating worker threads during I/O operations,
which under linux appear as separate processes. They *appear* to be
doing the same thing but you can't tell unless you connect a debugger to
each and take a stack trace :)

Phil.