‘keeping’ an already multi-user OS (which Haiku is) single user would require a rewrite…
More or less what is presently imposed by developer’s fiat, moreover, with the default user selection scripted, and the ability to add more than the basic few or change passwords presently locked-down. No change to that needed to suit what you are asking for.
Already provided for in the form of a separate identity for the sshd daemon.
I haven’t looked at what the httpd daemon runs as (PoorBoy?), but ‘top’ will show one that there are already separate credentials of one kind or another for several ‘team’ daemon-runners.
[quote]
So: single user for local machine, OR one network-user at a time, communicating with a UNIX based server daemon that manages logons / file quotas, etc. That way, Haiku remains a speedy, nimble single user desktop OS, but has a future as a workstation on a network, too.[/quote]
Haiku already supports multiple simultaneous ssh network sessions with different user ID’s from different remotes. Some fiddling required to set up the credentials, but it works well enough. No gain is taking it back out, either.
Generally, the physical count of kbd/video/mouse is going to limit most desktops to one user ‘at a time’ more pragmatically than the OS.
When it comes to ‘remote’, even CP/M on a Z80 could handle multiuser apps - and did so. They just had to be in the app, not the executive (Point Of Sale and BBS systems).
Anyway …
Single vs multi user design does not necessarily equate to speed differential or even code weight. More of that depends on how MUCH work is to be done at a given point in time than ‘for whom’ it is to be performed. Likewise, how much of that work is ‘bound’ by other-than code execution time.
Think waiting on keystrokes, mouse movements, HDD access, or network I/O. Not much work, unless your OS were to be 100% ‘polling’ driven…