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From: mac@esl.UUCP
Newsgroups: net.unix-wizards
Subject: Re: Location of partition table on disk
Message-ID: <334@esl.UUCP>
Date: Tue, 28-Oct-86 21:30:25 EST
Article-I.D.: esl.334
Posted: Tue Oct 28 21:30:25 1986
Date-Received: Wed, 29-Oct-86 22:07:54 EST
References: <8102@sun.uucp> <1073@cit-vax.Caltech.Edu>
Reply-To: mac@esl.UUCP (Mike McNamara)
Organization: ESL, Inc., Sunnyvale, CA.
Lines: 34

In article <1073@cit-vax.Caltech.Edu> mangler@cit-vax.Caltech.Edu (System Mangler) writes:
>In article <8102@sun.uucp>, mojo@sun.UUCP writes:
>> In the inode partitioning approach you have to have a file system open
>> (which means you have to know partitioning info) before you can read the
>> inode to get the partitioning info.
>
>
>The problem arises earlier in the boot process.  The first call to
>a 4.2bsd disk driver is not an open(), as you might expect; rather,
>it's an xxsize() call to determine the size of the primary swap
>partition.
>
>Putting the partition info in the inode is a great idea (no limit
>on the number of partitions) but the bootstrapping problems are real.
>It is dangerous to have one of your partitions defined separately,
>e.g. the swap partition defined in the kernel; it causes accidents.

	I remember beta testing a DG-UX system which you could tell,
	in the config file, the size you wanted the swap space to be.
	You could tell it any number, but it used 70,000 blocks.

	Made life real difficult if you tried to start /usr right after
	swap, and you spec'ed swap at < 70,000 blocks...

	we would bring it up single user, then quick adb the kernel.

	Life in the fast lane...

-- 
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| Michael Mc Namara                 |
| ESL Incorporated                  |
| ARPA: mac%esl.UUCP@ames.ARPA      |
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