Backup to DVD-R

Adrian Wontroba aw1 at
Wed Sep 21 05:42:15 BST 2005

On Tue, Sep 20, 2005 at 05:17:32PM +0100, Edmonds, Alan wrote:

> A long time ago in the distant past, I used a nice little buffering
> utility called 'ddd' for buffering cpio/tar output to quarter inch
> tape.  It might still be around.

The buffer port / package does much the same thing, quite well. I use
it to speed dump disc / network dumps.

Extract from man page:

       Buffer reads from standard input reblocking to the given blocksize  and
       writes each block to standard output.

       Internally buffer is a pair of processes communicating via a large cir-
       cular queue held in shared memory.  The  reader  process  only  has  to
       block  when  the queue is full and the writer process when the queue is
       empty.  Buffer is designed to try and keep the writer side continuously
       busy  so  that it can stream when writing to tape drives.  When used to
       write tapes with an intervening network buffer can result in a  consid-
       erable increase in throughput.

       The default settings for buffer are normally good enough.  If you are a
       heavy tape user then it is worth your while trying out various  differ-
       ent  combinations  of  options.  In particular running a buffer at both
       ends of the pipe can provide a substantial increase (see  last  example

Adrian Wontroba

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