Re: File System Performance

Ragnar Kjørstad
2001-11-12T22:31:53Z

On Mon, Nov 12, 2001 at 02:14:59PM -0800, Linus Torvalds wrote:
> > Seems not the case with gnu tar : write isn't even called once on the fd
> > returned by open("/dev/null",...). In fact a "grep write" on the strace
> > output is empty in the "tar cf /dev/null" case. Every file in the tar-ed
> > tree is stat-ed but no-one is read-ed.
>
> And what's the _point_ of the optimization? I've never heard of a "tar
> benchmark"..

Sure - it's called "amanda" :-)

I believe amanda run the backup once to /dev/null first to estimate the
size of the dataset, so it can make better use of the available tapes.

--
Ragnar Kjørstad
Big Storage