On Fri, 6 Feb 2004, Bryan Murdock wrote:
> On Fri, 2004-02-06 at 14:47, Ross Werner wrote:
> > On Fri, 6 Feb 2004, Von Fugal wrote:
> >
> > > Another variation on the classic tar/ssh combo
> > >
> > > ssh remote tar -czf /path/name | tar -xzf
> >
> > Doesn't ssh already use compression when sending data? Or is gunzip
> > preferable to ssh's compression?
>
> Only if you tell it to. I think the command line switch is -c. From
> what I read ssh's compression is only a time saver if you are on a slow
> modem link. I wonder if the above really saves you any time either.
My thoroughly unscientific tests have revealed:
(copying my "library" [21MB of well-compressing text files] over DSL)
Uncompressed: (scp -r [EMAIL PROTECTED]:'library/*' .)
12m24.748s
SSH Compression: (scp -C -r [EMAIL PROTECTED]'library/*' .)
6m48.366s
Gzip Compressing: (ssh [EMAIL PROTECTED] tar -czf - library/ | tar -xzf -)
5m34.531s
My conclusion: if you're transferring well-compressable stuff, and a lot
of it, sure, maybe it's worth it--but on the whole, it doesn't seem to be
worth the extra trouble. (I use "rsync -e ssh" whenever I'm transferring a
bunch of files like this anyway.)
~ ross
--
This sentence would be seven words long if it were six words shorter.
____________________
BYU Unix Users Group
http://uug.byu.edu/
___________________________________________________________________
List Info: http://uug.byu.edu/cgi-bin/mailman/listinfo/uug-list
