Re: git: ffaf862df662 - main - Mention that SILI makes tcopy(1) slow on modern tape drives

On Tue, 3 Sep 2024 10:45:36 GMT
Poul-Henning Kamp <phk@FreeBSD.org> wrote:

> The branch main has been updated by phk:
>
> URL: https://cgit.FreeBSD.org/src/commit/?id=ffaf862df662d507e8dd2667bffcba91e3745fe6
>
> commit ffaf862df662d507e8dd2667bffcba91e3745fe6
> Author:     Poul-Henning Kamp <phk@FreeBSD.org>
> AuthorDate: 2024-09-03 10:44:20 +0000
> Commit:     Poul-Henning Kamp <phk@FreeBSD.org>
> CommitDate: 2024-09-03 10:44:20 +0000
>
>     Mention that SILI makes tcopy(1) slow on modern tape drives
> ---
>  usr.bin/tcopy/tcopy.1 | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/usr.bin/tcopy/tcopy.1 b/usr.bin/tcopy/tcopy.1
> index da6a5231a843..f608e0af07e4 100644
> --- a/usr.bin/tcopy/tcopy.1
> +++ b/usr.bin/tcopy/tcopy.1
> @@ -97,6 +97,16 @@ command appeared in
>  .Sh BUGS
>  .Bl -item
>  .It
> +Modern tape drives may return a SCSI "Incorrect Length Indicator (ILI)"
> +for reach read with a different block size that what is on the

I assume this should be "for each read" and "size than what"

> +tape, and that slows things down a lot.
> +This can be disabled with the
> +.Xr mt 1
> +command:
> +.Bd -literal -offset indent
> +$ mt param sili -s 1
> +.Ed
> +.It
>  Writing an image of a tape to a file does not preserve much more than
>  the raw data.
>  Block size(s) and tape EOF marks are lost which would
>


--
Gary Jennejohn