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From: Stephen Fuld <sfuld@alumni.cmu.edu.invalid>
Newsgroups: comp.arch
Subject: Re: fuzzy disks, Is Parallel Programming Hard, And, If So, What Can
 You Do About It?
Date: Mon, 26 May 2025 13:36:30 -0700
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On 5/26/2025 11:58 AM, Stefan Monnier wrote:
> Stephen Fuld [2025-05-26 11:16:25] wrote:
>> https://www.seagate.com/innovation/multi-actuator-hard-drives/
> 
> Hmmm, hard to believe it makes commercial sense: if you need higher
> performance, when would this be price-competitive with an SSD?

It should be not much more costly than a single disk of the same 
capacity.  It has the same number of heads, platters, and of course the 
same enclosure, etc.  A little more work to separate the two arm 
magnetic actuators.  The same electronics, except for, and this is 
probably the most expensive part, an additional read channel.  So still 
a lot cheaper than an SSD.


> Also, that page is very light on details, but the image they include
> suggests the two actuators are used on separate platters, so it's akin
> to cramming a 2-disk-RAID0 into a single HDD enclosure.

Yeah, sort of.  But a single drive motor, a single host interface, 
microprocessor, etc.  So quite a bit less costly than two separate disks.


> Maybe part of the gain of having two actuators is that each actuator is
> a bit lighter?

I suspect that is insignificant.


-- 
  - Stephen Fuld
(e-mail address disguised to prevent spam)