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Question hard disk + case

adryman

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I use a USB 3.0 enclosure case + 2.5" HDD. After copying and reading files, I used the Windows eject function (safely remove hardware). After completing this command, when I tried to disconnect the USB3.0 cable from the PC, my hand hit the enclosure case and it moved a little on the table. Does this shock cause friction between the reading heads and the magnetic platters?

My HDDs are: 2013 models WDC WD10JPVX-08JC3T5, APPLE HDD HTS541010A99E662 and 2020 model Seagate ST500LM030.
The enclosure cases are: Orico 25PW1 black and Kesu 2530.

ejetar 3.png
 
Hard disks reportedly go through a 'drop test' from various heights onto various materials. The aim is to make it robust so they don't have platters getting gouged. Picture all around the world people bouncing their laptop computers on desktops or their laps, in vehicles, in backpacks. A nudge from your hand sounds rather minor. I also suspect that the heads were retracted before the computer said 'safe to eject'.
 
Disk operations, because they involve moving parts, take time to complete; the computer
operations that extend the file size, write the data, check the written bits for completeness,
and inform the operating system that the operation is complete, must all happen before disconnection
(or the operating system does not know the file system data on the disk is complete and consistent).

Because disconnection might interrupt power, and require some startup-and-identify steps,
it may be too late to complete the orderly process after the connector is disturbed.

When the 'safe eject' feature is invoked, there's a pause in access and presumably a 'safe-to-eject'
signal, which does not signify a mechanical safety achieved, but a data-consistent-and-complete
kind of safety, The mechanical friction issue is dealt with by various means, and applies
only with substantial accelerations (like, being struck by a hammer) rather than hand-fumbles.
Probably the loss-of-power at disconnect time makes a sequenced parking of the disk heads
in an orderly fashion, independent of any 'safe eject' command; the days when head/platter
crashes were likely to be destructive are behind us.
 
I have many doubts: some people say that enclosure case and Windows power settings and disconnecting the cables and cutting off the power have no influence on the parked heads of the 2.5" HDD after the Windows "safely remove hardware" eject command is completed and the letter E: disappears from the system; other people say the complete opposite and that the heads only park when cutting off the power to the enclosure case usb3.0+hdd2.5"; I'm confused.
 
Hi,

I have no general numbers, but the first source I found in the internet ... supports my own experience: SSDs are more durable.

In my company we suffered from repeated HDD fail, even different brands, high quality with good reputition.
More than 10 years ago we replaced all HDDs with SSDs and the problems are gone.
In PCs, in servers, in backup storage systems.

For sure I know: a single person´s experience is not a statistically reliable evindence.

Klaus
 
I used test HDD's for a living in the 80's where the benchmark was 10kh for MTBF which has improved by a factor of 10 now with glass disks and ferrofluidic smoother bearings. Then I had a few short-lived units after Y2K but now they are pretty reliable.
My oldest 3T drive is below. Then D,E is an 8T drive and C is an SSD.

They can be spun down manually with power left on and also by the power plan options, but the tray icon just flushes the cache and is pretty silent.

1733649566247.png
 
1) When the Windows "safely remove hardware" eject is invoked and the letter E: disappears from Windows, what type of command does Windows send to the 2.5" HDD and the HDD understands that it is time to park the heads?

2) Do the model, brand, chip of the USB3.0 enclosure case and Windows power settings have any relation to the parking of the heads of a 2.5" HDD after the Windows "safely remove hardware" eject command is completed and the letter E: disappears from the system?

3) In what year on 2.5" HDDs and in what version of Windows was parking the heads of 2.5" HDDs implemented after the Windows "safely remove hardware" eject command is completed and the letter E: disappears? even if the USB3.0 cable of the enclosure case remains connected to the PC/enclosure?
 
i think this is still an on-going debate. SSDs can lose charge, or can lose data due to an errant cosmic ray; HDD mechanical parts can fail sitting around for a long time (think greased bearings).

Although SSDs have many benefits compared to HDDs (consumption, speed, capacity, etc), it has been reported that in the lack of power for an extended period can degrade data; in doubt, I keep my external mass storage in HDDs.
 
Hi,

if I´m not mistaken...

"Safely remove hardware" just synchronizes OS cache to the HDD.
I don´t think it necessarily also parks the heads.

From internet:
"All the hard drives are provided with the mechanism of automatic parking at power supply turn off. Usually, the auto parking is carried out by the kinetic energy of magnetic disks rotation"

Klaus
 
If only the mechanisms would embody the progress that's possible at this point. My experience says 'it ain't there'. I believe the manufacturers are making little laptop hd's cheaper and not better. I had too many 2.5 inch drives fail (some in a laptop, some in external USB enclosures.) Admittedly years went by unused, since they're archival (or backups).

So today solid-state hd's are the big thing. My MacMini has SSD (500 GB) and it improves performance noticeably compared to the mechanical type (256 GB). I imagine SSD is where the handful of manufacturers are putting their R&D funds.
 

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