Erasing a 8.6 GB HD:

It takes about the same time as erasing a 3 TB HD.

Irony?

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Le 21/08/2012 15:15, Invisible a écrit :
> Erasing a 8.6 GB HD:
> 
> It takes about the same time as erasing a 3 TB HD.
> 
> Irony?


Same technology ? Interface ?

What do you mean by "erasing" ?
 * removing the partition table
 * overwriting the first few sectors with "dd if=/dev/null of=/dev/.. "
 * formatting again the partiton
 * overwriting the whole drive ?

Writing the whole 3 TB drive would take a few hours (at 50 to 100 MB/s,
I let you compute), if I trust the raid5 synchronisation on partitions
of 2TB that I observed.

The three former method are rather quick and might not have too much
impact by the disk size. (at worst, a few extra superblock to be written
along the disk)

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Invisible wrote:
> Erasing a 8.6 GB HD:
>
> It takes about the same time as erasing a 3 TB HD.

True, they both get crashed in few seconds/minutes, depending on 
available equipment.

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> Same technology ? Interface ?

Both IDE. Vastly different manufacture dates, though.

And that's the thing. Newer drives are much faster, but also much 
larger. So the erase time remains roughly constant.

> What do you mean by "erasing" ?
>   * removing the partition table

That takes milliseconds on any system.

>   * overwriting the whole drive ?

This.

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On 21/08/2012 02:15 PM, Invisible wrote:
> Erasing a 8.6 GB HD:
>
> It takes about the same time as erasing a 3 TB HD.

I take it back. The 8.6 GB drive is /still/ erasing...

I'm pretty sure that means I just have selected a non-optimal block size 
or something, because there's no way it should be taking this long.

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Le 24/08/2012 09:53, Invisible a écrit :
> On 21/08/2012 02:15 PM, Invisible wrote:
>> Erasing a 8.6 GB HD:
>>
>> It takes about the same time as erasing a 3 TB HD.
> 
> I take it back. The 8.6 GB drive is /still/ erasing...
> 
> I'm pretty sure that means I just have selected a non-optimal block size
> or something, because there's no way it should be taking this long.


It might have bad blocks, and enters a retry loop... with I/O timeout.

My best erasor: unix "dd bs=32kB if=/dev/zero of=/dev/<drive> "
If you really bother, provide a count= (but it's in block...)

If SMART is available on the drive, check it.

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On 24/08/2012 10:48 AM, Le_Forgeron wrote:
> It might have bad blocks, and enters a retry loop... with I/O timeout.

No, I think it's just ancient. (The OS still loads, after all...)

> My best erasor: unix "dd bs=32kB if=/dev/zero of=/dev/<drive>  "

Yeah, that's what I'm using. But with a 0.5 KB block size. For some 
reason, each block takes about 10 seconds...

I just tried changing it to 8 KB. Let's see if that makes any difference 
at all...

> If SMART is available on the drive, check it.

The drive is 8.6 GB. How ancient must that thing be? I doubt SMART was 
even invented back then...

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