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From: Clem Cole <clemc@ccc.com>
To: Paul Winalski <paul.winalski@gmail.com>
Cc: The Eunuchs Hysterical Society <tuhs@tuhs.org>, cctalk@classiccmp.org
Subject: Re: [TUHS] Ultrix Tape: Block Size?
Date: Tue, 16 Oct 2018 13:24:12 -0400	[thread overview]
Message-ID: <CAC20D2N-EW-A7RL3n0BSbW+aNmUmD5VnDtROzDR85feHth57Aw@mail.gmail.com> (raw)
In-Reply-To: <CABH=_VS-joYBV-+goBJKQwEDYgKbVgsJDuPxCVq+94Rhk2XnNg@mail.gmail.com>

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On Tue, Oct 16, 2018 at 12:57 PM Paul Winalski <paul.winalski@gmail.com>
wrote:

> The block size is almost certainly 512 bytes.
>
Which is what I said - the block siize is set by the HW.
But ... the issue is trying to get the TK-50 to stream.  Hence the
traditional unix: dd ibs=64K obs=XXX | tar xvfp -  trick.

This will tell the driver to read upto 128 blocks in one DMA and then pump
the bits into tar a 'XXX block' at a time (which is is usually 20b for
tar/cpio/dump et al and Ultrix obey's).
ᐧ

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  parent reply	other threads:[~2018-10-16 17:48 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-15 19:56 Warren Toomey
2018-10-15 21:00 ` Clem Cole
2018-10-15 21:01   ` Clem Cole
2018-10-15 21:34     ` Warner Losh
2018-10-16 16:57     ` Paul Winalski
2018-10-16 17:23       ` William Pechter
2018-10-16 17:34         ` Clem Cole
2018-10-16 17:34         ` Paul Winalski
     [not found]         ` <2658AACC-A451-4861-8CD8-F7E4BED8062A@comcast.net>
2018-10-17  6:14           ` [TUHS] TK50, was: " emanuel stiebler
2018-10-17 12:57             ` Tom Ivar Helbekkmo via TUHS
2018-10-18  7:48               ` Tom Ivar Helbekkmo via TUHS
2018-10-17 15:18             ` Clem Cole
2018-10-16 17:24       ` Clem Cole [this message]
2018-10-19 21:17       ` [TUHS] " Dave Horsfall
2018-10-15 21:52 ` Aaron Jackson

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