hpcg: merge weak scaling and add size experiment

The scaling.nix file defines both the strong and weak experiments by
using the parameter "enableStrong".

garlic/exp/hpcg/size.nix

@@ -0,0 +1,64 @@
+{
+  stdenv
+, stdexp
+, bsc
+, targetMachine
+, stages
+, garlicTools
+, callPackage
+}:
+
+with stdenv.lib;
+with garlicTools;
+
+let
+  common = callPackage ./common.nix { };
+
+  inherit (common) pipeline getSizePerTask;
+
+  # Initial variable configuration
+  varConf = {
+    sizeFactor = [ 1 2 4 8 16 32 ];
+  };
+
+  # Generate the complete configuration for each unit
+  genConf = c: targetMachine.config // rec {
+    expName = "hpcg-size";
+    unitName = "${expName}"
+    + "-nodes${toString nodes}"
+    + "-sf${toString sizeFactor}";
+
+    inherit (targetMachine.config) hw;
+
+    # hpcg options
+    inherit (c) sizeFactor;
+    gitBranch = "garlic/tampi+isend+oss+task";
+    nodes = 16;
+    totalTasks = ntasksPerNode * nodes;
+    sizePerCpu = { x = 2; y = 2; z = 4 * sizeFactor; };
+    sizePerTask = getSizePerTask cpusPerTask sizePerCpu;
+    nprocs = { x=1; y=1; z=totalTasks; };
+    blocksPerCpu = 4;
+    nblocks = blocksPerCpu * cpusPerTask;
+    ncomms = 1;
+    disableAspectRatio = true;
+
+    # Repeat the execution of each unit several times
+    loops = 5;
+
+    # Resources
+    qos = "debug";
+    time = "02:00:00";
+    cpusPerTask = hw.cpusPerSocket;
+    ntasksPerNode = hw.socketsPerNode;
+    jobName = unitName;
+  };
+
+  # Compute the array of configurations
+  configs = stdexp.buildConfigs {
+    inherit varConf genConf;
+  };
+
+in
+
+  stdexp.genExperiment { inherit configs pipeline; }