[Novalug] blocksize: tar piped over SSH to dd

[Richard Rognlie]

On Thu, May 17, 2007 at 01:12:18PM -0400, Ben Creitz wrote:
> If I have to tar a *huge* amount of files and send the result over SSH
> to dd, like this:
> 
>  tar cvf - big_dir | ssh me at remote "dd of=bkp.tar bs=xxx"
> 
> ... what is the ideal blocksize for dd? For tar?  Should I match them?
> Does it make a difference?

For disk to disk activities, it makes a big difference.  For network,
I don't know that it's as important.

something I would recommend is that you compress the data stream.

either with

	tar cvfz - big_dir | ssh me at remote "dd of=bkp.tar.gz"

or perhaps in the ssh session itself with "ssh -C"

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