[clug] Disk size

[Paul Wayper]

On 28/08/18 14:28, Eyal Lebedinsky via linux wrote:
> I thought we need some comic relief after the recent fun on the hill. Not
> Linux specific but...
> 
> For a while now I noticed that recently acquired USB disks offer less storage
> than advertised.
> 
> For example, a 32GB disk
>     SanDisk Ultra USB 3.0 Flash Drive 64GB
> provides (as fdisk tells)
>     Disk /dev/sdj: 57.9 GiB, 62109253632 bytes, 121307136 sectors
> 
> A smaller one
>     SanDisk Ultra Fit USB 3.0 Flash Drive 32GB
> has
>     Disk /dev/sdj: 28.7 GiB, 30752636928 bytes, 60063744 sectors
> 
> I just now saw a message (unrelated) on the linux-raid list mentioning:
>     "I should note that for some reason the "32G" Optane only has 29.260 G
>     bytes (27.3 GiB)"
> So SSDs are afflicted too.
> 
> What is this trend? The GB/Gib excuse ran out of steam? What is it now?

No, that's the same excuse.  Permanent storage makers provide storage in
powers of thousands of bytes; RAM (which gets most value for money where as
many of the address bus lines needed are in use) in powers of 1024 bytes.

I believe hard drive manufacturers used to include the 'spare' sectors that
were used for reallocating bad sectors, but now don't.

I'd get used to it, I don't think the industry is going to change :-)

Have fun,

Paul