[TUHS] Clever code

[Bakul Shah]

On Dec 13, 2022, at 8:14 AM, Ralph Corderoy <ralph at inputplus.co.uk> wrote:
> 
> Hi Bakul,
> 
>> Fortune 32:16 was a 5.6Mhz machine and couldn't process 1020KB/sec
>> (17 sectors/track of early ST412/ST506 disks) fast enough.  As Warner
>> said, one dealt with it by formatting the disk so that the logical
>> blocks N & N+1 (from the OS PoV) were physically more than 1 sector
>> apart.
> 
> Sticking with ST506 hard drives, by the time the 8 MHz ARM2 from Acorn
> was reading a 56 MB Rodime, it was the drive which couldn't keep up so
> executables were stored compressed on disk so the CPU had something to
> do, uncompressing the sector's content, while it waited for the next
> sector to arrive.  :-)

IIRC the slow part was due to running some common apps! Not much buffering
allowed on a 256KB machine so by the time the app asks for the next block,
on a 1:1 interleave the block would be past the read head and you had to
spend an extra revolution to grab it!