[9fans] Real time Glenda

[9fans] Real time Glenda

[Don Bailey]

Has anyone attempted to create a real time version of Plan 9? What would this effort require? Would substantial changes to the kernel be needed?

D

Re: [9fans] Real time Glenda

[Andreas Wagner]

http://doc.cat-v.org/plan_9/real_time/

On Sat, Apr 21, 2012 at 3:38 PM, Don Bailey <don.bailey@gmail.com> wrote:
> Has anyone attempted to create a real time version of Plan 9? What would this effort require? Would substantial changes to the kernel be needed?
>
> D

Re: [9fans] Real time Glenda

[Iruatã Souza]

On Sat, Apr 21, 2012 at 4:38 PM, Don Bailey <don.bailey@gmail.com> wrote:
> Has anyone attempted to create a real time version of Plan 9? What would this effort require? Would substantial changes to the kernel be needed?
>
> D

http://doc.cat-v.org/plan_9/real_time/

Re: [9fans] Real time Glenda

[Lyndon Nerenberg]

From proc(3):

	  period nu Set	the real-time scheduling period	of the process
		    to nu, where n is an optionally signed number con-
		    taining an optional	decimal	point and u is one of
		    s, ms, us, µs, ns,	or empty.  The time is inter-
		    preted, respectively, as seconds, milliseconds,
		    microseconds, microseconds,	nanoseconds, or, in
		    the	case of	an absent units	specifier, as
		    nanoseconds. If the	time specifier is signed, it
		    is interpreted as an increment or decrement	from a
		    previously set value.  See also the	admit command
		    below.

	  deadline nu
		    Set	the real-time deadline interval	of the process
		    to nu, where n and u are interpreted as for	period
		    above.

	  cost nu   Set	the real-time cost (maximum CPU	time per
		    period) of the process to nu, where	n and u	are
		    interpreted	as for period above.

	  sporadic  Use	sporadic scheduling for	the real-time process.
		    The	description of the admit command below con-
		    tains further details.

	  yieldonblock
		    Make the real-time process yield on	blocking I/O.
		    The	description of the admit command below con-
		    tains further details.

	  admit	    Given real-time period, deadline and cost are set
		    (an	unset deadline will set	deadline to period),
		    perform a schedulability test and start scheduling
		    the	process	as a real-time process if the test
		    succeeds.  If the test fails, the write will fail
		    with error set to the reason for failure.