On 20180628 04:38, Martin Steigerwald wrote:
Martin Steigerwald - 28.06.18, 13:30:
jdow - 28.06.18, 12:00:
On 20180628 01:16, Martin Steigerwald wrote:
[…]
That brings to the fore an interesting question. Why bother with
RDBs
over 2TB unless you want a disk with one single partition? This
Win10
monster I am using has a modest BIOS driver partition for the OS
and
a giant data partition. That smaller partition would easily work
with
any RDB/Filesystem combination since 2.0. So there are some good
workarounds that are probably "safer" and at least as flexible as
RDBs, one Linux has used for a very long time, too.
Well, my use case was simple:
I had this 2 TB disk and I choose to share it as a backup disk for
Linux *and* AmigaOS 4.x on that Sam440ep I still have next to me
desk here.
EEEEEEK! The hair on my neck is standing up straight! Have you heard
of SAMBA? The linux mail server firewall etc machine has an extra
4TB
disk on it as a backup for the other systems, although a piddly 4TB
is small when I save the entire 3G RAID system I have. It's a proof
of concept so.... A full backup on a 1gig Ethernet still takes a
looooong time. But backing up even an 18GB disk on an Amiga via
100Base-t isn't too bad. And disk speeds of the era being what they
were it's about all you can do anyway.
Heh, the thing worked just fine in Amiga OS 4. I got away with it
without an issue, until I plugged the disk to my Linux laptop and
wrote data onto the Linux file system. Mind you, I think in that
partition marked LNX\0 I even created a Linux LVM with pvcreate. Do
you call that insane? Well it probably is. :)
And as an Amiga user I could just return to you: I clicked it, it did
not warn, so all is good :)
But yeah, as mentioned I researched the topic before. And I think
there
has not even been an overflow within the RDB:
The raw, theoretical limit on the maximum device capacity is about
2^105 bytes:
32 bit rdb_Cylinders * 32 bit rdb_Heads * 32 bit rdb_Sectors * 512
bytes/sector for the HD size in struct RigidDiskBlock
http://wiki.amigaos.net/wiki/RDB_(Amiga_Rigid_Disk_Block)
Confirmed by:
The .ADF (Amiga Disk File) format FAQ:
http://lclevy.free.fr/adflib/adf_info.html#p6
But what do I write, you know the RDB format :)
So just do the calculation in 96 Bit and you all are set :)
For sectors.
Or
3*32+9 (for 512 bytes per sector) = 105 bits
for bytes.
Now that is a reason for 128 Bit CPUs :).
Muuhahaha.
And if you make the logical block size 65536 you need 128 bits or 10^something
big = 2^128.
{^_-}
