SMP Version of tar

[Peter Pentchev]

On Mon, Oct 08, 2012 at 08:38:33AM +0200, Wojciech Puchar wrote:
> >>gzip cannot - it is single stream.
> >
> >gunzip commutes with cat, so gzip
> >compression can be multi-threaded
> >by compressing separate blocks and
> >concatenating the result.
> 
> right. but resulting file format must be different.

Not necessarily.  If I understand correctly what Tim means, he's talking
about an in-memory compression of several blocks by several separate
threads, and then - after all the threads have compressed their
respective blocks - writing out the result to the output file in order.
Of course, this would incur a small penalty in that the dictionary would
not be reused between blocks, but it might still be worth it.

G'luck,
Peter

-- 
Peter Pentchev	roam at ringlet.net roam at FreeBSD.org peter at packetscale.com
PGP key:	http://people.FreeBSD.org/~roam/roam.key.asc
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Hey, out there - is it *you* reading me, or is it someone else?
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