How many tasks can be started?

Adam Lackorzynski adam at
Wed Mar 14 21:14:08 CET 2007


On Tue Mar 13, 2007 at 14:13:32 +0100, Daniel Vandersee wrote:
> can you tell me how many Tasks can be started from L4? As the task id
> has 11 bit, the theoretical maximum seems to be 2048, but if I configure

This is the theoretical limit, yes.

> simple_ts to use 246 tasks, I can't create a new task without using
> simple_ts (I use rmgr_get_task and rmgr_task_new). In this case the
> first free task number is 256.

simple_ts reserves those tasks (task numbers). So you observation is ok.

> The task creation via rmgr_task_new seems
> to work (a valid task id is returned), but it seems that I can't serve
> the first page fault. If I serve it with an fpage, I immediately get the
> same page fault again and again. With simple_ts configured to 245 tasks
> everything works fine.

I don't quite get this. You create task 256 via rmgr and sending
pagefaults does not work but it does work when descreasing simple_ts
tasks by one? Have a demo program?

Adam                 adam at

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