From: Martin Quinson <martin.quinson@loria.fr>
Date: Thu, 15 Jun 2017 15:36:21 +0000 (+0200)
Subject: try to fix the impact of a big full VM on its PM
X-Git-Tag: v3.16~84
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/864618094efa422a18a6e4837b234f5b5a940652

try to fix the impact of a big full VM on its PM
---

diff --git a/src/plugins/vm/VirtualMachineImpl.hpp b/src/plugins/vm/VirtualMachineImpl.hpp
index d9371762d4..39487a8e60 100644
--- a/src/plugins/vm/VirtualMachineImpl.hpp
+++ b/src/plugins/vm/VirtualMachineImpl.hpp
@@ -95,6 +95,7 @@ public:
   e_surf_vm_state_t getState();
   void setState(e_surf_vm_state_t state);
   static std::deque<s4u::VirtualMachine*> allVms_;
+  int coreAmount() { return coreAmount_; }
 
   bool isMigrating = false;
 
diff --git a/src/surf/HostImpl.cpp b/src/surf/HostImpl.cpp
index 72f0f72f68..b212a1692f 100644
--- a/src/surf/HostImpl.cpp
+++ b/src/surf/HostImpl.cpp
@@ -29,24 +29,14 @@ void HostModel::ignoreEmptyVmInPmLMM()
 {
   /* iterate for all virtual machines */
   for (s4u::VirtualMachine* ws_vm : vm::VirtualMachineImpl::allVms_) {
-
     Cpu* cpu = ws_vm->pimpl_cpu;
+    int active_tasks = lmm_constraint_get_variable_amount(cpu->constraint());
 
-    int is_active = lmm_constraint_used(cpu->model()->getMaxminSystem(), cpu->constraint());
-
-    if (is_active) {
-      /* some tasks exist on this VM */
-      XBT_DEBUG("set the weight of the dummy CPU action on PM to 1");
-
-      /* FIXME: If we assign 1.05 and 0.05, the system makes apparently wrong values. */
-      ws_vm->pimpl_vm_->action_->setPriority(1);
+    /* The impact of the VM over its PM is the min between its vCPU amount and the amount of tasks it contains */
+    int impact = std::min(active_tasks, ws_vm->pimpl_vm_->coreAmount());
 
-    } else {
-      /* no task exist on this VM */
-      XBT_DEBUG("set the weight of the dummy CPU action on PM to 0");
-
-      ws_vm->pimpl_vm_->action_->setPriority(0);
-    }
+    XBT_INFO("set the weight of the dummy CPU action of VM%p on PM to %d (#tasks: %d)", ws_vm, impact, active_tasks);
+    ws_vm->pimpl_vm_->action_->setPriority(impact);
   }
 }