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From: John Levine <johnl@taugh.com>
Newsgroups: comp.arch
Subject: Re: ancient OS history, ARM is sort of channeling the IBM 360
Date: Tue, 25 Jun 2024 04:04:31 -0000 (UTC)
Organization: Taughannock Networks
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According to Lawrence D'Oliveiro  <ldo@nz.invalid>:
>How much of theoretical disk bandwidth was the filesystem capable of 
>using? Because I know early Unix systems were pretty terrible in that 
>regard, until Berkeley’s “Fast File System” came along.

My recollection is that if you were using QSAM with multiple buffers
and full track records it wasn't hard to keep the disk going at full
speed. Later versions of OS do chained scheduling if you have enough
buffers, doing several disk operations with one cnannel program.

-- 
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly