Xref: utzoo comp.unix.wizards:6997 comp.unix.questions:6042
Path: utzoo!mnetor!uunet!husc6!uwvax!umn-d-ub!umn-cs!mmm!ems!pwcs!daveg
From: daveg@pwcs.StPaul.GOV (Dave Glowacki)
Newsgroups: comp.unix.wizards,comp.unix.questions
Subject: Re: Compressing unix disks
Message-ID: <4336@pwcs.StPaul.GOV>
Date: 10 Mar 88 23:54:14 GMT
References: <1071@ndmath.UUCP> <305@marconi.SW.MCC.COM> <1097@hubcap.UUCP>
Reply-To: daveg@pwcs.StPaul.GOV (Dave Glowacki)
Followup-To: comp.unix.wizards
Organization: City of St. Paul Public Works
Lines: 20

In article <1097@hubcap.UUCP> hubcap@hubcap.UUCP (Mike Marshall) writes:
>For the benefit of the poster of the original question: BSD 4.2's fast file
>system uses a disk management scheme that keeps disk transfer rates near
>constant over time (not sensitive to fragmentation through use). 4.2 BSD's
>throughput rates are dependent, instead, on the total amount of free space,
>which must not be allowed to drop below a certain threshold. 

What is this threshold?

Doing a 'df' shows that the system reserves 10% of each partition, since
the amounts in the used and available columns only add up to 90% of the
total blocks in each partition.  My boss maintains that 10% of the
AVAILABLE blocks must be kept free, leaving us with only about 81% of the
total disk space.  I think that the system's already got the space it needs.

Could someone PLEASE tell me I'm right, so we can get back all that wasted
space?  (9% of 3 Fuji Eagles)
-- 
Dave Glowacki           daveg@pwcs.StPaul.GOV         ...!amdahl!ems!pwcs!daveg
                   Disclaimer: Society's to blame.