[mythtv-users] Single partition or whole disk

f-myth-users at media.mit.edu f-myth-users at media.mit.edu
Tue Jul 3 08:37:58 UTC 2012


Btw, I've noticed that, when copying from a large local disk to
another empty directory (e.g., when rsync is doing nothing but copying
blocks), I often get much better performance by using "cp -a" instead.
rsync doesn't seem nearly as efficient when the job is just "copy
absolutely everything"; it uses significantly more CPU than cp, even
though "just copy the file" should be the same amount of work in
either.  I conclude that a lot more time was spent optimizing cp for
its one task in life.

Of course, after that initial copy, rsync will be much faster, because
it will only be copying new files or new pieces of files.  And I often
do "cp -a" and then follow up with an rsync just in case I've missed
something somehow; if there's nothing to do, it will be almost instant.

So if you've just started the copy, and you're impatient, try cp and
see if your performance goes up.  (Might, might not, depends on
whether you're bottlenecked at the disk, the disk interface, or
on the CPU.  But 60 MB/sec is actually probably not as fast as
these drives can go; I think I've seen higher transfer rates on mine.)


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