Block devices
Hey, I've got a book that talks about block devices in Freebsd 3.4. I got curious and went looking for some, but my 4.8 distro doesn't seem to have any. When did they disappear? Why did they leave? Will they ever return? I poked around in google and freebsd.org but didn't turn anything up. Curious... Jeff ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Block devices
Jeff Shevlen [EMAIL PROTECTED] writes: I've got a book that talks about block devices in Freebsd 3.4. I got curious and went looking for some, but my 4.8 distro doesn't seem to have any. When did they disappear? Why did they leave? Will they ever return? I poked around in google and freebsd.org but didn't turn anything up. Curious... They disappeared four or five years ago because they were unnecessary. The character mode devices support everything that block devices did... The technical discussion was probably on the -CURRENT and -ARCH mailing lists, around the summer of '98. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Block devices
On Fri, Nov 28, 2003 at 12:03:42PM -0500, Lowell Gilbert wrote: Jeff Shevlen [EMAIL PROTECTED] writes: I've got a book that talks about block devices in Freebsd 3.4. I got curious and went looking for some, but my 4.8 distro doesn't seem to have any. When did they disappear? Why did they leave? Will they ever return? I poked around in google and freebsd.org but didn't turn anything up. Curious... They disappeared four or five years ago because they were unnecessary. The character mode devices support everything that block devices did... The technical discussion was probably on the -CURRENT and -ARCH mailing lists, around the summer of '98. ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED] Thanks. There was one other poster who mentioned the threads in -ARCH. I took a look, but a digest was more what I was after... ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Block Devices
Hey, I've got a book that talks about block devices in Freebsd 3.4. I got curious and went looking for some, but my 4.8 distro doesn't seem to have any. When did they disappear? Why did they leave? Will they ever return? I poked around in google and freebsd.org but didn't turn anything up. Curious... Jeff ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: Block Devices
On Mon, Nov 24, 2003 at 07:39:38PM -0500, Jeff Shevlen wrote: Hey, I've got a book that talks about block devices in Freebsd 3.4. I got curious and went looking for some, but my 4.8 distro doesn't seem to have any. When did they disappear? They disappeared from FreeBSD 4-CURRENT in Nov 1999. (So they aren't in any of the 4.x releases.) Why did they leave? I am not sure, but if you check the archives for the freebsd-arch mailing list there was a long discussion about this in Oct. 1999 that might answer your question. Will they ever return? Unlikely. I poked around in google and freebsd.org but didn't turn anything up. Curious... Checking the CVS commitlogs and mailing-list can turn up quite a bit of information. -- Insert your favourite quote here. Erik Trulsson [EMAIL PROTECTED] ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to [EMAIL PROTECTED]
Character Devices vs. Block Devices
Hello, A quick ls of my dev directory revealed that each one of my hard drives is considered a character device by the system. Example: crw-r- 2 root operator 116, 0x00010002 Aug 19 16:09 /dev/ad0 crw-r- 2 root operator 116, 0 Aug 19 16:09 /dev/ad0a crw-r- 2 root operator 116, 1 Aug 19 16:09 /dev/ad0b crw-r- 2 root operator 116, 2 Aug 19 16:09 /dev/ad0c crw-r- 2 root operator 116, 3 Aug 19 16:09 /dev/ad0d crw-r- 2 root operator 116, 4 Aug 19 16:09 /dev/ad0e crw-r- 2 root operator 116, 5 Aug 19 16:09 /dev/ad0f crw-r- 2 root operator 116, 6 Aug 19 16:09 /dev/ad0g crw-r- 2 root operator 116, 7 Aug 19 16:09 /dev/ad0h What I am confused about, aren't hard drives treated as block devices on most systems? What am I missing? Regards, Weston To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message
Re: Character Devices vs. Block Devices
From: Weston M. Price [EMAIL PROTECTED] Date: Tue, 1 Oct 2002 15:19:59 + Sender: [EMAIL PROTECTED] Hello, A quick ls of my dev directory revealed that each one of my hard drives is considered a character device by the system. Example: crw-r- 2 root operator 116, 0x00010002 Aug 19 16:09 /dev/ad0 crw-r- 2 root operator 116, 0 Aug 19 16:09 /dev/ad0a crw-r- 2 root operator 116, 1 Aug 19 16:09 /dev/ad0b crw-r- 2 root operator 116, 2 Aug 19 16:09 /dev/ad0c crw-r- 2 root operator 116, 3 Aug 19 16:09 /dev/ad0d crw-r- 2 root operator 116, 4 Aug 19 16:09 /dev/ad0e crw-r- 2 root operator 116, 5 Aug 19 16:09 /dev/ad0f crw-r- 2 root operator 116, 6 Aug 19 16:09 /dev/ad0g crw-r- 2 root operator 116, 7 Aug 19 16:09 /dev/ad0h What I am confused about, aren't hard drives treated as block devices on most systems? What am I missing? Nothing. I can't comment on most systems, but block devices were eliminated from FreeBSD in V4. R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634 To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message
Re: Character Devices vs. Block Devices
So, given this, I am assuming that hard drives are treated as raw devices exclusively? That is, no intermediate buffers are maintained between the user process and the device: From The Design and Implementation of the 4.4 BSD operating system: The character interface does not copy the user data into a kernel buffer before putting then on an I/O queue. Rather, it arranges to have the I/O done directly to or from the address space of the process. Is this valid on FreeBSD? Regard, Weston On Tuesday 01 October 2002 03:19 pm, Weston M. Price wrote: Hello, A quick ls of my dev directory revealed that each one of my hard drives is considered a character device by the system. Example: crw-r- 2 root operator 116, 0x00010002 Aug 19 16:09 /dev/ad0 crw-r- 2 root operator 116, 0 Aug 19 16:09 /dev/ad0a crw-r- 2 root operator 116, 1 Aug 19 16:09 /dev/ad0b crw-r- 2 root operator 116, 2 Aug 19 16:09 /dev/ad0c crw-r- 2 root operator 116, 3 Aug 19 16:09 /dev/ad0d crw-r- 2 root operator 116, 4 Aug 19 16:09 /dev/ad0e crw-r- 2 root operator 116, 5 Aug 19 16:09 /dev/ad0f crw-r- 2 root operator 116, 6 Aug 19 16:09 /dev/ad0g crw-r- 2 root operator 116, 7 Aug 19 16:09 /dev/ad0h What I am confused about, aren't hard drives treated as block devices on most systems? What am I missing? Regards, Weston To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message
Re: Character Devices vs. Block Devices
On Tue, 1 Oct 2002, Weston M. Price wrote: So, given this, I am assuming that hard drives are treated as raw devices exclusively? That is, no intermediate buffers are maintained between the user process and the device: Nope, there is buffering for the file system interface. I dont remember the exact reasons for nuking the block devices, but I think it has to do with the new VM subsystem and the integrated buffer cache/VM, but my memory may be failing. If you want a more acurate answer, search the archives for -hackers and -current Is this valid on FreeBSD? Nope. The book was written before FreeBSD nuked block devices. Fer Regard, Weston On Tuesday 01 October 2002 03:19 pm, Weston M. Price wrote: Hello, A quick ls of my dev directory revealed that each one of my hard drives is considered a character device by the system. Example: crw-r- 2 root operator 116, 0x00010002 Aug 19 16:09 /dev/ad0 crw-r- 2 root operator 116, 0 Aug 19 16:09 /dev/ad0a crw-r- 2 root operator 116, 1 Aug 19 16:09 /dev/ad0b crw-r- 2 root operator 116, 2 Aug 19 16:09 /dev/ad0c crw-r- 2 root operator 116, 3 Aug 19 16:09 /dev/ad0d crw-r- 2 root operator 116, 4 Aug 19 16:09 /dev/ad0e crw-r- 2 root operator 116, 5 Aug 19 16:09 /dev/ad0f crw-r- 2 root operator 116, 6 Aug 19 16:09 /dev/ad0g crw-r- 2 root operator 116, 7 Aug 19 16:09 /dev/ad0h What I am confused about, aren't hard drives treated as block devices on most systems? What am I missing? Regards, Weston To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message To Unsubscribe: send mail to [EMAIL PROTECTED] with unsubscribe freebsd-questions in the body of the message
