Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.arch
Subject: Re: Is Parallel Programming Hard, And, If So, What Can You Do About
 It?
Date: Sat, 17 May 2025 23:57:50 -0000 (UTC)
Organization: A noiseless patient Spider
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On Mon, 12 May 2025 22:35:57 -0000 (UTC), I wrote:

> In other words, telling lies to the OS that the write has completed
> when it hasn’t. This kind of thing can really stuff up filesystem
> integrity guarantees.

What do you know, it turns out there is this feature, originally from
SCSI and part of NCQ, called “Force Unit Access” (FUA)
<https://en.wikipedia.org/wiki/Disk_buffer#FUA>.

But do we really know that the drive vendors will honour this command
.... ?