"The Linux 2.6.23 kernel comes with a modular scheduler core and a Completely Fair Scheduler, which is implemented as a scheduling module. In this article, get acquainted with the major features of the CFS, see how it works, and look ahead to some of the expected changes for the 2.6.24 release."
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Member since:2006-03-20
Well, if a scheduler wants to be fair to users, then a user with a heavy computation must not be treated in an unfair manner against a user with a lighter computation. Therefore, it's not fair to equalize a user with 48 processes to a user with 4 processes.
Member since:2006-02-15
Well, if a scheduler wants to be fair to users, then a user with a heavy computation must not be treated in an unfair manner against a user with a lighter computation. Therefore, it's not fair to equalize a user with 48 processes to a user with 4 processes.
Yes, it is. The scheduler has no way of knowing which user has more mission-critical processes running, and each user's processes are important to them ie. you have no right to say "My processes are more important than yours so my processes run first!". Besides, the scheduler also has no way of knowing what the "heavy computation" (taken from your example) is used for: it could either be used for for example to calculate some molechular patterns, or it could just as well just be some pretty fancy and demanding screensaver. Would it then be fair that a user ran a very fancy and demanding screensaver with lots of heavy computation and robbed your lighter processes of their CPU time?
Member since:
2005-07-24
This is the sort of topic where people could go on arguing ad infinitum while establishing nothing. Define the parameters of the problem first. Is the goal to be fair to processes or to users? Depending upon what you decide there, the answer pretty much falls out on its own.
I suppose it depends upon the context of the situation. For my purposes as admin of XDMCP servers serving out desktops being fair to people is best for me. However, IO scheduling is at least as important, if not more important, than processor scheduling for my workloads. But processor scheduling tends to get more press.