New Linux scheduler old Solaris one(s)
By Darrenmoffat-Oracle on Aug 03, 2007
I find it interesting and slightly sad, given how low level a topic this really is, how much is being written about the new CFS scheduler being introduced into Linux. The sad part is how much flamage is flying around as a result of this from people not in the slightest bit involved in the desgin and development - this sadly is the ugly side of many open source groups.
OpenSolaris has multiple scheduling classes as well, actually Solaris had this and OpenSolaris inherited it when the source was opened up - but there is active work in this area going on, and the ability to realtively easily add more. You can also change the dispatch tables of the existing ones - even on a live running system (see dispadmin(1M) and ts_dptbl(4)
As you hopefully see from Eric's presentation the scheduler is only a small part of the over all resource management issue and ensuring fairness. OpenSolaris builds on the scheduler by using things like processor pools. I particularly like the Fair Share Scheduler (FSS) class. The Sun Ray server that I use at work (and at home via VPN) uses FSS so that users can't dominate the server cpu resources.
I find it very cool that you can even use different scheduling classes for zones (actually you can do it per process but mixing FSS with TS/IA in a given processor pool isn't recommended). If all that wasn't cool enough all the policy for FSS (and much other projects stuff related to resource management) can be stored in LDAP so it is easy to implement a network wide policy.