Date: Sun, 23 Apr 2006 12:37:16 +0700 From: "Angka H. K." <harikurniawan@gmail.com> To: current@freebsd.org, sos@freebsd.org Subject: Re: acd(4) and maximum read block size Message-ID: <4c40c4e70604222237w1f6778b2j4a2fc0ff1f7df730@mail.gmail.com> In-Reply-To: <20060421180626.GA28049@roadrunner.buck.local> References: <20060421180626.GA28049@roadrunner.buck.local>
next in thread | previous in thread | raw e-mail | index | archive | help
I have concern about it but my case is different.
I have a disk that burn using 6.1-current and it burn good no error with 6.=
1.
But when I read it on 7.0 it produce error ("i am not quite remember but
something with big..., like reading error sector"). The disk still readable
but the access is slow.
On 4/22/06, Ulrich Spoerlein <uspoerlein@gmail.com> wrote:
>
> S=F8ren, group,
>
> I'm working on some improvements for recoverdisk[1] to handle optical
> media
> better. I found it an invaluable tool for recovering old CD-Rs. It also
> helps with newer DVDs, when your drive sucks wrt. error recovery.
>
> recoverdisk tries to read in 1MB, 64kB and SECTORSIZE chunks. This has
> the obvious drawback, that it can't really handle audio CDs or mode 2
> CDs with a sectorsize of 2352.
>
> While this is easily fixed, the acd(4) driver seems to allow no reads
> greater than 128kB *for audio CDs*. While this is also not terrible, it
> results in roughly 700 error messages per CD, as all the 1MB (1046640
> bytes, more precisely) chunks will fail.
>
> A side note: Accessing audio CDs via atapicam and dd(1) is completely
> impossible. Is the SCSI subsystem limited to multiple-of-512-blocksizes?
>
> [1] /usr/src/tools/tools/recoverdisk
>
> Ulrich Spoerlein
> --
> PGP Key ID: 20FEE9DD Encrypted mail welcome!
> Fingerprint: AEC9 AF5E 01AC 4EE1 8F70 6CBD E76E 2227 20FE E9DD
> Which is worse: ignorance or apathy?
> Don't know. Don't care.
>
>
>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4c40c4e70604222237w1f6778b2j4a2fc0ff1f7df730>