Re: cdrecord produces broken CDs on -CURRENT: The Answer !
Christoph Herrmann wrote: > > The Problem was the use of vfs.ioopt=2 ! > As long as vfs.ioopt is 1 or 2 the CDs are broken and with > vfs.ioopt=0 the CDs are o.k. > > I didn't see any other problems with the use of vfs.ioopt=2, > especially no Filesystem corruption :-). Are there other known > problems withs vfs.ioopt != 0 ? Yes, it breaks read(2) semantics totally. With a traditional system, if you read something into your buffer, it never changes. With vfs.ioopt >= 1, that read may be turned into a mmap() if the conditions are right. Specifically, if you are doing a page aligned read of one or more pages, your original page will be released and you will get a copy-on-write page mapped in. The problem with that is that it is copy-on-write for *you*, not everybody else. If somebody else subsequently changes the file, your buffer will automagically change. This is why it is off. The NFS zerocopy patches made some changes to the VM and buffer system to fix this. It was pretty simple to fix if I recall correctly. Cheers, -Peter -- Peter Wemm - [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED] "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
Re: cdrecord produces broken CDs on -CURRENT: The Answer !
On 28 Nov, Christoph Herrmann wrote: > > The Problem was the use of vfs.ioopt=2 ! > As long as vfs.ioopt is 1 or 2 the CDs are broken and with > vfs.ioopt=0 the CDs are o.k. > > I didn't see any other problems with the use of vfs.ioopt=2, > especially no Filesystem corruption :-). Are there other known > problems withs vfs.ioopt != 0 ? At the time I tested this, native netscape died with a bus error (or segfault?, don't remember). Bye, Alexander. -- There's no place like ~ http://www.Leidinger.net Alexander @ Leidinger.net GPG fingerprint = C518 BC70 E67F 143F BE91 3365 79E2 9C60 B006 3FE7 To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
Re: cdrecord produces broken CDs on -CURRENT: The Answer !
On Wed, Nov 28, 2001 at 15:44:37 +0100, Christoph Herrmann wrote: > > The Problem was the use of vfs.ioopt=2 ! > As long as vfs.ioopt is 1 or 2 the CDs are broken and with > vfs.ioopt=0 the CDs are o.k. > > I didn't see any other problems with the use of vfs.ioopt=2, > especially no Filesystem corruption :-). Are there other known > problems withs vfs.ioopt != 0 ? I'm sort of surprised you didn't see any filesystem corruption with vfs.ioopt turned on -- physio uses the same mechanism as the pass(4) driver for getting data into and out of the kernel. (vmapbuf()) Matt Dillon said almost a year ago that the vfs.ioopt code was broken, but you'd have to ask him to explain it, I don't remember what the problem was. Ken -- Kenneth Merry [EMAIL PROTECTED] To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
cdrecord produces broken CDs on -CURRENT: The Answer !
The Problem was the use of vfs.ioopt=2 ! As long as vfs.ioopt is 1 or 2 the CDs are broken and with vfs.ioopt=0 the CDs are o.k. I didn't see any other problems with the use of vfs.ioopt=2, especially no Filesystem corruption :-). Are there other known problems withs vfs.ioopt != 0 ? Ciao Christoph &:-) To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
