Re: Tree based scheduling

Rauli Ruohonen (raulir@voimax.voima.jkl.fi)
Mon, 19 Jan 1998 11:40:17 +0200

In linux-kernel Pavel Machek wrote:
>Bad idea, when done this way. Imagine system with two users (A, B),
>each runs cpu-intensive task, A1, B1, and some interactive tasks (A2,
>B2). Now, if scheduling is done like that, both users will be given
>time in big chunks (I assume), so 500msec user-1's A1 will run, and at

You assume incorrectly :)

>that time A2 will give good response time, and then 500msec B1 will
>run, and A2 will starve.
>
>This would work ok with current scheduler. You may avoid this problem,
>somehow, but I do not know how to do that.

The users would be given one normal time-slice at a time, e.g.

<proc1 of user1> runs 1/100th of a second
<proc1 of user2>...
<proc2 of user1>
<proc1 of user2>
<proc1 of user1>
<proc1 of user2>..

if user1 has 2 processes and user2 has one process.