[throwaway798214]

I think your requirements are quite contradictory; my old Commodore 64 had a lean operating system or basically no operating system at all. Yet it took me nearly half an hour to load a single 40 kilobyte game from tape (only to see it didn't work so I had to try loading it again).

What I'm saying is you're not after a lean operating system - you're after fast I/O and that you can get with money. Also the lag you mention is not about operating systems, it's about apps. My "ls" startup is pretty fast:

  $ time ls
  Desktop  Documents  Downloads  Music  Pictures  Videos  bin  code

  real    0m0.006s
  user    0m0.000s
  sys     0m0.000s

[sargstuff]

REU : https://www.c64-wiki.com/wiki/RAMDrive

'lean' operating system/software usage setup small enough to fit /run entirely in ram (and/or 100MB+ cpu lvl 1 cache) would avoid i/o issues. --power backup not optional.

[throwaway798214]

Offtopic but lately I've been building a "new" physical C64 which is nearly done - SD2IEC + Epyx Fastload for fast disc emulation and Kung Fu Flash for near instant .prg loading. Related to the discussion I think KFF is faster to load a .prg than my Windows is loading an .exe - not that I would ever do actual work on a C64 with or without KFF.

[sargstuff]

GEOS[0] under VICE[1] / qnx[2] on latest top of the line amd cpu pretty minimal software fluff at cost of lot of wasted/idle cpu.

[0] : https://www.lyonlabs.org/commodore/onrequest/geos/index.html

[1] : https://vice-emu.sourceforge.io/vice_2.html

[2] : https://vice-emu.sourceforge.io/qnx.html

[dcminter]

Off topic, but...

> it took me nearly half an hour to load a single 40 kilobyte game from tape

Surely that's a bit pessimistic? It was around 5 minutes for the ZX Spectrum, the Commodore wasn't a slower baud rate was it?

[tdeck]

According to Wikipedia

> Because of its digital format the [Commodore C2N] Datasette is both more reliable than other data cassette systems and very slow, transferring data at around 50 bytes per second.

That's about 400 baud.

Another page suggests the Spectrum's real speed was about 13604 baud.

https://sinclair.wiki.zxnet.co.uk/wiki/Spectrum_tape_interfa...

[dcminter]

Wow, TIL! Thanks!