Post by J. P. Gilliver (John)
I have a brand-new "1T" (of course thus only 931.5G) drive. (It is now
showing 158 hours on time.)
When I run HDTune, I get a huge gouge from about 11-23%, and some in the
first 3%, about which I'm somewhat concerned: surely a brand-new drive
can't be this bad? (The SMART data actually showed 0 for hours the first
time I looked, and I have stored looks that then showed 4 hours and now
15x; it came in a sealed bag; and the label on the drive itself says
November 2017. I _imagine_ all these things can be faked, though I
imagine the SMART one requires special knowledge/equipment; however,
I've no real reason to suspect the trader I bought it from - and
besides, 1T 2.5" haven't been around _that_ long, have they?)
However, it has just occurred to me that the gouges correspond to where
I actually have data: I have it partitioned into C:, which is 71.6G of
99.9G free, and D:, which is 723G of 831G free. [Is there a setting in
explorer to show used rather than free?]
Since the gouges correspond rather well to where my data is, I wonder if
that's their reason. Also, the remainder of the HDTune graph is fairly
flat, whereas the ones I've seen people post usually tail down towards
the end, so I'm wondering if I've got HDTune - or some other setting in
the computer (BIOS?) - set at sub-optimum, such that it's (a) limiting
the maximum (the flat line is at about 170 MB/sec - is that low? - and
the "gouge" is at about 90), and (b) making HDTune drop where there's
actually something on the disc. I'm quite happy with the performance of
the computer, and all other tests including "Very long test (~4 min)"
from http://www.softwareok.com/?Microsoft/IsMyHdOK say it's OK. (I
haven't run HDTune's non-quick error scan yet, as that clearly will take
hours; I'll set it going tonight if I remember.)
It's an HGST (I think that's Hitachi/Toshiba combined?) HTS541010B7E610,
according to HDTune [I deliberately went for a "5400" rather than a
"7200"], and (again according to HDTune) apparently supports UDMA Mode 6
(Ultra ATA/133), with Active being UDMA Mode 5 (Ultra ATA/100). The PC
is a Toshiba Portégé R700-1F5.
It's possible for a drive to have a "wear" pattern.
The place where say, an OS lives, can cause a lot of reallocations
just in that area. When HDTune runs over it, the reallocations take
longer to read, and cause the visible "gouge" symptoms. I had to
replace a drive here, just because the OS portion (72GB approx)
had become too slow to use. Reallocations still read out as "0".
Benchmarking is a more sensitive test than looking for Reallocation
raw data of 0. You can have a gouge in a drive, the drive can "feel"
slow, and Reallocations still reads 0 and the overall drive health
will use a superlative.
And yes, of course drives leave the factory with defects already
patched. No drive leaves the factory without reallocations already
on there. There is an "acceptance" value for defects. If the drive
is below that limit, "ship it". For example, there might already
be 100,000 reallocations as it slips out the door.
When Reallocations data becomes non-zero, you're looking at some "slice"
of ill health, rather than receiving a totally unbiased report. In the
example here, we only find out about the N reallocations as the
drive is approaching end of life. The value of N is high enough,
the user runs out to the store and buys another. The drive is
acceptable to the factory, anywhere in the "0" area. The
drives I was watching here, the percent life said the
N would span 0..5500 or so as a raw value. Above 5500, one
would guess that visible CRC errors and retired NTFS clusters
would be the result. Once the Service Area (Track -1) is
unreadable, the drive should stop being detected.
|<------- 0 ------->| "N" | "~dead..."
The first hard drives, the full height drives which were 3.5"
high, they had "factory" and "grown" errors. I used to get
drives, and dump the "factory" list and print it on a piece
of paper (pasted inside the computer chassis). The fact there
was a "factory" list tells you the "factory" knew about them.
And during the testing/verifying phase at the factory, sectors
were already being reallocated. On those drives, you could
reset the "grown" defects and let the reallocation algo
re-detect them. Which worked pretty well (I tested it, because
that's the kind of guy I am). There weren't a lot of grown
that weren't re-detected that way, so the ones it had detected,
really were bad. Modern IDE drives do not support that interface
and once a sector is reallocated on an IDE/SATA drive, it's
like that forever (or until the factory refurbishes the drive
HGST appeared out of no-where one day. There was some announcement
of the consumer part of the IBM disk business, being part of the
new venture. With it, went some IBM scientists. The IBM staff
were responsible for the HGST web pages, the ones that explained
how modern drives worked, and what wizmo material science
was being used. I don't know what hand Hitachi had in all
of it. Japanese companies don't typically have those sorts
of web pages, explaining how they do stuff. It was the IBM
people doing that. HGST was later bought by Western Digital.
There was an article on Anandtech in the last couple years,
where it listed who bought who, and it's possible the
only three brands left are WDC, Seagate, and Toshiba.
HGST drive may still keep their branding, but WDC is the
corporate master now. I don't know whether the IBM staff
go back to IBM or what happens to them.
This article actually sums up what happened, in a paragraph or two.
What these articles don't typically cover, is what happened to the people.