HTCondorWiki: How To Match Multicore After Drain

 **How to match only Multicore jobs in recently drained slots**
 
+Known to work with HTCondor version: 8.2.8
+
 Since the purpose of the defrag daemon is to drain jobs on a p-slot so multi-core jobs can begin to match, it would be best to implement a policy where recently drained p-slots can *insist* on matching only multicore jobs for a period of time.
 
 Unfortunately, there is no attribute that uniquely identifies a recently drained slot - but there are two candidate attributes that come close with some caveats.
@@ -11,31 +13,29 @@
 
 *This is the preferred policy - use this policy if you use the defrag daemon*
 {code}
- # This knob must be set in the negotiator's configuration. it prevents
- # slots from going into matched state, which is works fine and is necessary
+ # This knob must be set in the negotiator's configuration. It prevents
+ # slots from going into matched state, which works fine and is necessary
  # to make the $(StateTimer) trigger only when we leave draining state.
 NEGOTIATOR_INFORM_STARTD = false
 
- # A job counts as multicore when it requests 4 or more core, or when
- # it has already matched to a slot that has less than 4 cores.
+ # Set OnlyMulticoreInterval to the number of seconds the startd should
+ # only allow multi-core jobs. Default to about 2 negotiation cycles.
+OnlyMulticoreInterval = 2*$(NEGOTIATOR_INTERVAL:300)
+ # If this slot has more than 4 cores free, then insist on jobs that
+ # request at least 4 core or more.
 IsMulticore = RequestCpus >= IfThenElse(Cpus<4,1,4)
- # We want to insist on multicore jobs for about 2 negotiation cycles
-OnlyMulticoreInterval = 2*$(NEGOTIATOR_INTERVAL:60)
  # This is already defined in the default config, included for here for clarity
 StateTimer = (time() - EnteredCurrentState)
- # Ignore the policy for non p-slots
+ # We only want this policy to apply to partitionable slots (pslots)
 IsntUnmatchedPSlot = PartitionableSlot=!=true || State=="Matched"
 
-OnlyMulticoreJobsAfterDrain = $(IsntUnmatchedPSlot) || $(IsMulticore) || $(StateTimer) > $INT(OnlyMulticoreInterval)
+OnlyMulticoreJobsAfterDrain = $(IsntUnmatchedPSlot) || $(IsMulticore) || $(StateTimer) > $(OnlyMulticoreInterval)
 
 START = $(START) && ( $(OnlyMulticoreJobsAfterDrain) )
 {endcode}
 
 The policy says that for 2 negotiation cycles after the STARTD starts up or leaves draining state, the slot should only match jobs that want at least 4 cores. Once the slot has less than 4 available Cpus remaining, it will match single-core jobs.  We only want this portion of the START expression to be evaluated by the Negotiator, which is what the $(IsntUnmatchedPSlot) sub-expression does.
 
-Note for 8.2 and earlier versions: change =$INT(OnlyMulticoreInterval)= to =$(OnlyMulticoreInterval)=
-
-
 *Alternate policy that triggers whenever the p-slot fully drains for any reason - but doesn't work at all if draining is only partial*
 
 This policy using =ExpectedMachineGracefulDrainingCompletion= triggers the preference for multi-core automatically whenever a p-slot has no child d-slots, but, it reverts back to matching any job as soon as there are child d-slots.
@@ -50,7 +50,7 @@
  # note that if the result is < 0, draining is in the future.
 DrainStateTimer = (time() - ExpectedMachineGracefulDrainingCompletion)
 
-OnlyMulticoreJobsAfterDrain = PartitionableSlot=!=true || $(IsMulticore) || $(DrainStateTimer) > $INT(OnlyMulticoreInterval) || $(DrainStateTimer) < 0
+OnlyMulticoreJobsAfterDrain = PartitionableSlot=!=true || $(IsMulticore) || $(DrainStateTimer) > $(OnlyMulticoreInterval) || $(DrainStateTimer) < 0
 
 START = $(START) && ( $(OnlyMulticoreJobsAfterDrain) )
 {endcode}