(I
suspect that here is a case where you use rsync because it's easier to
figure out rsync
that to use something (actually quite different) that is more
"appropriate".
hmm... ok, I am open to suggestions! What do you recommend
that would be more appropriate? One thing I am currently investigating
is "File Alteration Monitor" or fam, which was alluded to somewhere in this
lists archives.
The
"something more appropriate" is something you design and write
yourself.
And
you get to debug it yourself. Including all the little suble thingees which
are there and do matter.
They
are at least theoretically possible.
I
wouldn't say I recommend them.
If
everything goes perfectly, a lot of things are equivalent.
It's
when things mess up in the middle, what is the resultant state? What should it
be?
This
is really a question of which errors do you commit (to try to avoid other
errors)
Question: how long does it take to write a file to
disk?
Answer: It depends ... actually on EVERYTHING that is going on
DURING the write.
Generally disk is written much faster if it is written
sequentially.
One
way to slow it way way down, it to interrupt the stream of writes with a bunch
of (any) disk IO elsewhere on the disk.
You
should realize that disk is called random access, but is in fact anything but
random.
Like
scheduled trains or busses or airplanes, the place under the heads that is to
be read or written comes up very predictably. This means that tiny
changes can have big consequences. Miss a flight by a few seconds and
wait for the next day (or week or ...). Most likely you have the drive
reading in one place and writing in a different place and the seek time has a
significant impact on what happens.
