format/newfs larger external consumer drives

[Don whY]

On 7/10/2015 9:59 AM, Wojciech Puchar wrote:
>> When building a filesystem (FFS) on these 1/2/3/4TB external USB
>> drives, any suggestions?  E.g., changing block sizes?  Cut into
>> multiple slices to make fsck's job easier (as well as *recovery*)?
>
> i would assume you will most likely store large files.

For the demo application I'm writing up (to illustrate the issues
that appliance developers might face), I would be storing large files
(e.g., ISO's).  But, some other developer/application might choose
to use the medium for smaller files -- or even smaller media capacity.

So, I'm trying to prepare a list of criteria to guide them in configuring
the medium as well as their expectations from it.  E.g., the "big" drives
I mentioned tend to use 4K "sectors" while smaller/legacy drives are 512.
I don't know if this can all be transparent to the user or if the
developer needs to take special steps based on the actual medium being
supported.

The limited bandwidth of the comm channel to the (external) drive
means little "mismatches" in configuration can have noticeable
impact on the end user (e.g., he opts for finer-grained management
and pays the price when a volume isn't properly dismounted, power
fail, etc.)

> newfs -m 0 -i 262144 -b 65536 -f 8192 -U /dev/yourdisk
>
> and it will be fast to fsck.
>