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8.0: Timers; Scheduler Sluggishness; Remote Terminal Status Line

    Date: Sat, 09 Jun 90 09:21:27 EDT
    From: rjb1@gte.com

    We've finally upgraded most of our machines to 8.0.  Now the
    inevitable simple questions begin:

    1.  Is there any way to get a list of pending timers?  The "old
    timers" are still in their queue, but the new ones aren't.  Even with
    the quite lucid documentation of the new scheduler (some Symbolics
    tech writer deserves a pat on the back), and with an apropos of the
    process package, I can't figure out how to examine all the new timers
    to decide whether my nightly utilities are already waiting.  I can map
    over the processes, but how can I get from a process to its timer
    without maintaining my own mapping?

Peek Processes mode has a "Timers" heading; click on it and you'll see
all the new-style timers.

    2.  Even before I contaminate the system with my kludgey old polled
    processes, the new scheduler seems to get horribly bogged down, just
    switching among activities.  I'm in the habit of simultaneously
    firing-up a compile-system or two, starting an individually-filtered
    mapped-over move in Zmail, and then getting down to work in Zmacs.
    This sort of activity always slowed things down a bit, but now it
    seems intolerable.  The scheduler seems too "fair" about sharing the
    processor among these activities.  Has anyone developed a scheduler
    policy (is that what I want?) that greatly favors the "current"
    activity?  (Admittedly, I'm running on a '40; perhaps if we upgraded
    our hardware....  But that's "a whole nother" story.)

I've noticed this, too.  The old scheduler had per-process quantum
settings; the quantum is the amount of time a process runs before it can
be preempted.  Interactive processes frequently got quantum boosts, I
believe, which made them appear snappier.

Unfortunately, there's no documentation on how to extend the "Extensible

    3.  Has anyone used the remote terminal on 8.0?  Successfully?  It
    _tries_ to do some really clever things, but none of my terminal
    emulators seem to quite cope -- or else it's doing something wrong.
    Perhaps I'm overly optimistic to think that a vt320 supports ANSI
    X3.<whatever> -- does anybody have a terminal type on which this
    works?  Or, if that's not the problem, has anyone hacked this code
    into submission?

I don't think there have been any major changes to the remote terminal's
use of X3.64 escape sequences in 8.0.  It has always had the bug that it
uses "ESC backquote" to move the cursor within the current line, and no
terminal or emulator I know of (except for Symbolics's) supports this
escape sequence (X3.64 is simply a dictionary of control sequences, but
it doesn't specify a required vocabulary, nor is there a way for a host
to find out the supported vocabulary of a terminal).

    (For those who haven't tried it, the remote terminal can now include a
    status line on the bottom of the screen, not unlike what you see on
    the console, complete with an underlined noting-progress -like
    indicator.  But now, when it gets confused, it sticks in underlining
    mode and generously decorates the screen, among other, more familiar

I've never seen this.  The failure mode I notice is that when command
completion in the CP is rewriting what you've typed so far (e.g. to
capitalize the command name) it does it in the wrong place because of
the above "ESC backquote" problem.