Bad clusters on one partition

[craigm]

Steve Gibson, the creator of Spinrite, explains that over time the
heads can drift from the position they had when the data was first
written to the sector. As a result the now mis-aligned heads can
no longer access that data and thus the sector may be marked as
"bad." The DynaStat component of SpinRite jolts the heads across
the platter in an attempt to locate those heads back over the
place the data was written. It then reads that data and rewrites
it. Here's how it's explained in the SpinRite documentation:

"During this exhaustive rereading, DynaStat employs its second
recovery strategy of deliberately wiggling the drive's heads. By
successively approaching the troubled sector from different
distances and directions, the heads arrive at the sector's track
at different velocities, which in turn produce small but
significant displacements in the head's resting position. This
allows DynaStat to compensate for the long-term alignment drift
that occurs in non-servo based drives, and the positioner
hysterysis that occurs in servo-based designs.
Thus the drive's heads are given every opportunity to land in the
best possible location to correctly read the sector. This approach
is also extremely effective at recovering data from misaligned
diskettes – which SpinRite 3.1 is proving to be extremely
effective upon."

You can hear the clattering sounds from the hard drive when
SpinRite does its thing. It's a great program and I highly
recommend it to people who are trying to extract valuable data
from "bad" sectors.

See "SpinRite's Technology" on this page:
http://www.grc.com/srdocs.htm

OK, I thought that was what you would say.

For non embedded servo drive, the heads could drift over time and
temperature. This is due to the stack up of mechanical drifts and
temperature coefficients of the materials.

However, as an issue with disk drives, drives produced in the last 15+ years
have used embedded servo. The servo information is on the same track as the
data. (Data sectors are placed between the servo bursts.)

To have the sector written on the disk to _not_ be under the path of the
head means that it was not written in the correct position or the heads are
in the wrong position when reading.

The cause of this is mechanical vibration during the read or write process.
There is also some small offset due to noise in the system.

All modern drives have error recovery mechanisms that use retries to read
the data. Many of these retries apply offsets to the servo system to deal
with mispositioned data.

Given this, the only benefit from SpinRite or other data recovery programs
is the fact that it makes additional attempts to read the data from a given
sector. A drive may make 50 or 100 attempts to read a sector before it
gives up. (This depends upon the recovery algorithm specific to the drive.)
Each subsequent read attempt by SpinRite invokes another set of attempts by
the drive.

In other words, all the talk of seeking away and returning by the recovery
program are just meaningless.

There was a time when hard drives used stepper motors to position the heads.
Controllers at the time also had limited error recovery. In that timeframe,
recovery programs may have useful. But for today's hard drives, it is
really in the hands of the drive.

On the other hand, floppies still use stepper motors and the SpinRite
recovery techniques can be useful.

 

[SgtMinor]

Nonsense, you should never use it on a drive that has only hours to live.
You will kill it almost instantly.

That's an excellent point. SpinRite should only be used on drives
with at least two days' worth of life left in them.

 

[Rod Speed]

Rod Speed wrote

Nope.

The OP asked about using it which implied he had a copy.

Nope. He could just as easily be asking whether its worth buying.

In that case it's ALWAYS worth using as it does no harm.

Complete waste of time, it cant do what you claim it does.

You don't know what you're talking about.

Fraid so. What you claim isnt even possible with a servo drive.

I speak from experience.

No you dont with that stupid claim about the r/w heads.

Having recovered data from several bad disks, and having removed
so-called "bad sectors" from others, I don't feel scammed in the least.

Pity that all modern hard drives can remove bad sectors themselves.

They dont need Spinrite to do that.

I have owned and used various versions of SpinRite for over 15 years and I don't know of anything
that can revive hard drives the way it can.

Your pig ignorance is your problem.

 

[Meat Plow]

That's an excellent point. SpinRite should only be used on drives with at
least two days' worth of life left in them.

Personally I only run Spinrite if the drive has no more than 2.35 days of
life left.

 

[Rod Speed]

craigm wrote

Steve Gibson, the creator of Spinrite, explains that over time the heads can drift from the
position they had when the data was first written to the sector.

And you're so stupid/pig ignorant that you dont even realise
that while that was a real effect with stepper motor drives,
it doesnt happen with servo drives. And we aint seen
stepper motor head actuators for DECADES now.

AND the sectors dont actually drift, the problem is that the
heads dont always end up in the same place so you get
sector jitter around the track with stepper motor drives.

As a result the now mis-aligned heads can no longer access that data and thus the sector may be
marked as "bad."

Doesnt happen with servo drives.

The DynaStat component of SpinRite jolts the heads across the platter in an attempt to locate
those heads back over the place the data was written.

Not even possible.

It then reads that data and rewrites it. Here's how it's explained in the SpinRite documentation:

And you're so stupid that you dont even realise
what a scam/con job that is with servo drives.

"During this exhaustive rereading, DynaStat employs its second
recovery strategy of deliberately wiggling the drive's heads. By successively approaching the
troubled sector from different
distances and directions, the heads arrive at the sector's track at different velocities, which in
turn produce small but
significant displacements in the head's resting position.

Not even possible with servo drives.

This allows DynaStat to compensate for the long-term alignment drift that occurs in non-servo
based drives,

Pity none of your drives are non-servo based drives.

Pity none of those have been made for DECADES now.

and the positioner hysterysis that occurs in servo-based designs.

Bare faced lie.

Thus the drive's heads are given every opportunity to land in the
best possible location to correctly read the sector. This approach is also extremely effective at
recovering data from misaligned diskettes

Irrelevant to hard drives, stupid.

– which SpinRite 3.1 is proving to be extremely effective upon."

Irrelevant to hard drives, stupid.

You can hear the clattering sounds from the hard drive when SpinRite does its thing.

Anyone can thrash the heads around, stupid.

Only fools are actually stupid enough to buy Gibson's bullshit.

It's a great program

Nope, its an expensive scam/con job.

and I highly recommend it to people who are trying to extract valuable data from "bad" sectors.

You have always been, and always will be, completely and utterly
irrelevant. What you might or might not 'recommend' in spades.

See "SpinRite's Technology" on this page:
http://www.grc.com/srdocs.htm

No thanks, there is only so much mindless silly shit anyone should have to put up with.

 

[Rod Speed]

Folkert Rienstra wrote
Correct.

Gets sillier by the minute.

That's an excellent point. SpinRite should only be used on drives with at least two days' worth
of life left in them.

And just how do you propose to determine that with a particular drive, child ?

 

[SgtMinor]

Personally I only run Spinrite if the drive has no more than 2.35 days of
life left.

I think that you and I and Folkert may be the only people who know
where to get that info. And I ain't tellin'.

 

[SgtMinor]

Nope. He could just as easily be asking whether its worth buying.




Complete waste of time, it cant do what you claim it does.




Fraid so. What you claim isnt even possible with a servo drive.




No you dont with that stupid claim about the r/w heads.




Pity that all modern hard drives can remove bad sectors themselves.

Do they defrag themselves too? Funny stuff!

 

[Rod Speed]

Rod Speed wrote

Do they defrag themselves too?
Nope.

Funny stuff!

Pathetic stuff in your case.

 

[Folkert Rienstra]

OK, I thought that was what you would say.

Yup, that is what 30 years of experience will do to you.

[snip]

 

[Folkert Rienstra]

Still posting reply-to addresses, I see, Dykes.

Asking a question that could be asked in any post, but no, you had to
specifically choose mine.

[snip]

What does spinrite claim to do?

 

[Arno Wagner]

SgtMinor wrote:

Can you explain what you mean about not being in the path of the r/w heads?

That is complete nonsense. The heads can reach every part of the
usable surface. They have not been stepper-positioned by about 2
decades now.

Arno

 

[Arno Wagner]

Steve Gibson, the creator of Spinrite, explains that over time the
heads can drift from the position they had when the data was first
written to the sector. As a result the now mis-aligned heads can
no longer access that data and thus the sector may be marked as
"bad." The DynaStat component of SpinRite jolts the heads across
the platter in an attempt to locate those heads back over the
place the data was written. It then reads that data and rewrites
it. Here's how it's explained in the SpinRite documentation:

LOL! That is completely impossible with moving-coil head actuators!
In very old (2 decades and more) stepper based designs, this was
indeed an issue, but not anymore. It was also an issue with some
floppy disk drives.

Arno

 

[Arno Wagner]

That's an excellent point. SpinRite should only be used on drives
with at least two days' worth of life left in them.

And how would you know in advance? .... Oops, you cannot!

Arno

 

[Folkert Rienstra]

LOL! That is completely impossible with moving-coil head actuators!

Of course it is possible, you mindless babblebot.
When the drive writes it fixes it's head position between servo bursts.
When something goes wrong during that time and the head moves from it's
radial position then the data isn't where it is supposed to be on a read.
It's mindless stuff that the error correction can likely cope with but
that doesn't mean that it can't 'possibly' happen.