From 3f94d1b260808a7a23fa1e2d6e90f2a2d56116ed Mon Sep 17 00:00:00 2001
From: Gerhard Theurich <theurich@sourcespring.net>
Date: Wed, 25 Sep 2024 17:51:50 +0000
Subject: [PATCH] Small optimizations for large petCounts.

---
 src/Infrastructure/VM/src/ESMCI_VM.C                      | 5 +++++
 .../StateReconcile/src/ESMF_StateReconcile.F90            | 8 ++++++++
 2 files changed, 13 insertions(+)

diff --git a/src/Infrastructure/VM/src/ESMCI_VM.C b/src/Infrastructure/VM/src/ESMCI_VM.C
index db32a1532f..e609585189 100644
--- a/src/Infrastructure/VM/src/ESMCI_VM.C
+++ b/src/Infrastructure/VM/src/ESMCI_VM.C
@@ -140,6 +140,10 @@ static bool esmfFinalized = false;
 #undef  ESMC_METHOD
 #define ESMC_METHOD "ESMCI::VMKeyCompare()"
 static bool VMKeyCompare(unsigned char *vmKey1, unsigned char *vmKey2){
+  if (vmKey1==vmKey2) return true;  // quick return for identical pointers
+#if 1
+  return std::memcmp(vmKey1, vmKey2, vmKeyWidth) == 0;
+#else
   int i;
   for (i=0; i<vmKeyWidth; i++)
     if (vmKey1[i] != vmKey2[i]){
@@ -147,6 +151,7 @@ static bool VMKeyCompare(unsigned char *vmKey1, unsigned char *vmKey2){
     }
   if (i==vmKeyWidth) return true;
   return false;
+#endif
 }
 
 #undef  ESMC_METHOD
diff --git a/src/Superstructure/StateReconcile/src/ESMF_StateReconcile.F90 b/src/Superstructure/StateReconcile/src/ESMF_StateReconcile.F90
index f528d56c39..ed296abb3c 100644
--- a/src/Superstructure/StateReconcile/src/ESMF_StateReconcile.F90
+++ b/src/Superstructure/StateReconcile/src/ESMF_StateReconcile.F90
@@ -197,6 +197,12 @@ subroutine ESMF_StateReconcile(state, vm, rc)
           rcToReturn=rc)) return
     end if
 
+#if 0
+    ! cleaner timings below, eliminating issue due to different times PETs enter
+    ! BUT: only enable this for testing purposes
+    call ESMF_VMBarrier(localvm, rc=localrc)
+#endif
+
     ! Determine whether there is anything to be Reconciled at all.
     ! If not then return as quickly as possible
 
@@ -534,6 +540,8 @@ recursive subroutine StateReconcileIsNoopLoc(stateR, isNoopLoc, rc)
 #endif
           if (.not.isNoopLoc) exit  ! exit for .false.
 
+          vmId = vmIdItem  ! more likely to hit pointer comparison this way
+
         enddo
 
         deallocate(itemNameList)