The fixed resource estimator provides a fixed size revocable pool: if you tell it to create a 24 cpu revocable pool, there will be a 24 cpu revocable pool. It is not looking at utilization slack.
On Mon, Aug 6, 2018 at 2:28 PM, Varun Gupta <var...@uber.com> wrote: > Hi, > > I was reading the code > <https://github.com/apache/mesos/blob/master/src/slave/resource_estimators/fixed.cpp#L57> > for fixed resource estimator and want to understand the behavior for it. > > For example, CPU is the only revocable resource for the Mesos Cluster. I > have one machine with 24 CPUs as non-revocable, and correspondingly 24 > CPU's are revocable resources (hardcoded for fixed resource estimator). > > Below are two scenario's, I want to confirm what is the actual behavior or > it is completely different. > > 1) Static behavior, were on 24 CPU revocable and 24 CPU non-revocable, 12 > CPU non-revocable task is launched with 100% utilization. In this scenario, > resources offered 12 CPU non-revocable + 24 CPU revocable resources. > > 2) Same as above scenario, and reading the document > <https://docs.google.com/document/d/1r1WCHgmPJp5wbrqSZLsgtxPNj3sULfHrSFmxp2GyPTo/edit#> > for Revocable resources for Aurora. *"A revocable CPU resource value will > include unallocated + unused resource"*. For above scenario, fixed > resource estimator should return 12 CPU non-revocable and 12 CPU revocable > (as 12 CPU non-revocable are running on 100% utilization). > Following up this scenario, suppose 12 CPU non-revocable task is launched > and of that 8 CPU are effectively used. Thereby, offer generated will be 12 > CPU non-revocable and 12 (available) + 4 (usage slack) CPU revocable > resources. > > Thanks, > Varun > >
