Re: [RFC 3/5] sched: Add CPU rate hard caps

From: Peter Williams
Date: Thu Jun 01 2006 - 19:43:19 EST


Balbir Singh wrote:
Kirill Korotaev wrote:
Using a timer for releasing tasks from their sinbin sounds like a bit
of an overhead. Given that there could be 10s of thousands of tasks.



The more runnable tasks there are the less likely it is that any of them is exceeding its hard cap due to normal competition for the CPUs. So I think that it's unlikely that there will ever be a very large number of tasks in the sinbin at the same time.

for containers this can be untrue... :( actually even for 1000 tasks (I suppose this is the maximum in your case) it can slowdown significantly as well.

Do you have any documented requirements for container resource management?
Is there a minimum list of features and nice to have features for containers
as far as resource management is concerned?



Is it possible to use the scheduler_tick() function take a look at all
deactivated tasks (as efficiently as possible) and activate them when
its time to activate them or just fold the functionality by defining a
time quantum after which everyone is worken up. This time quantum
could be the same as the time over which limits are honoured.

agree with it.

Thinking a bit more along these lines, it would probably break O(1). But I guess a good
algorithm can amortize the cost.

It's also unlikely to be less overhead than using timers. In fact, my gut feeling is that you'd actually be doing something very similar to how timers work only cruder. I.e. reinventing the wheel.

--
Peter Williams pwil3058@xxxxxxxxxxxxxx

"Learning, n. The kind of ignorance distinguishing the studious."
-- Ambrose Bierce
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