Run all Windows jobs in a single worker image

Jenkinsfile-win64

@@ -10,6 +10,15 @@ def commit_id   // necessary to pass a variable from one stage to another
 
 pipeline {
   agent none
+
+  // Setup common job properties
+  options {
+    timestamps()
+    timeout(time: 240, unit: 'MINUTES')
+    buildDiscarder(logRotator(numToKeepStr: '10'))
+    preserveStashes()
+  }
+
   // Build stages
   stages {
     stage('Jenkins Win64: Initialize') {
@@ -40,8 +49,7 @@ pipeline {
       steps {
         script {
           parallel ([
-            'test-win64-cpu': { TestWin64CPU() },
-            'test-win64-gpu-cuda10.1': { TestWin64GPU(cuda_target: 'cuda10_1') }
+            'test-win64-cuda10.0': { TestWin64() },
           ])
         }
         milestone ordinal: 3
@@ -66,7 +74,7 @@ def checkoutSrcs() {
 }
 
 def BuildWin64() {
-  node('win64 && build && cuda10') {
+  node('win64 && cuda10_unified') {
     unstash name: 'srcs'
     echo "Building XGBoost for Windows AMD64 target..."
     bat "nvcc --version"
@@ -107,48 +115,23 @@ def BuildWin64() {
   }
 }
 
-def TestWin64CPU() {
-  node('win64 && cpu') {
+def TestWin64() {
+  node('win64 && cuda10_unified') {
     unstash name: 'srcs'
     unstash name: 'xgboost_whl'
     unstash name: 'xgboost_cli'
-    echo "Test Win64 CPU"
+    echo "Test Win64"
     echo "Installing Python wheel..."
     bat "conda activate && (python -m pip uninstall -y xgboost || cd .)"
     bat """
     conda activate && for /R %%i in (python-package\\dist\\*.whl) DO python -m pip install "%%i"
     """
     echo "Installing Python dependencies..."
     bat """
-     conda activate && conda install -y hypothesis && conda upgrade scikit-learn pandas numpy hypothesis
+     conda activate && conda install -y hypothesis && conda upgrade scikit-learn pandas numpy hypothesis  && python -m pip install cupy-cuda100
     """
     echo "Running Python tests..."
     bat "conda activate && python -m pytest -v -s --fulltrace tests\\python"
-    bat "conda activate && python -m pip uninstall -y xgboost"
-    deleteDir()
-  }
-}
-
-def TestWin64GPU(args) {
-  node("win64 && gpu && ${args.cuda_target}") {
-    unstash name: 'srcs'
-    unstash name: 'xgboost_whl'
-    unstash name: 'xgboost_cpp_tests'
-    echo "Test Win64 GPU (${args.cuda_target})"
-    bat "nvcc --version"
-    echo "Running C++ tests..."
-    bat "build\\testxgboost.exe"
-    echo "Installing Python wheel..."
-    bat "conda activate && (python -m pip uninstall -y xgboost || cd .)"
-    bat """
-    conda activate && for /R %%i in (python-package\\dist\\*.whl) DO python -m pip install "%%i"
-    """
-    echo "Installing Python dependencies..."
-    def cuda_short_ver = args.cuda_target.replaceAll('_', '')
-    bat """
-     conda activate && conda install -y hypothesis && conda upgrade scikit-learn pandas numpy hypothesis  && python -m pip install cupy-${cuda_short_ver}
-    """
-    echo "Running Python tests..."
     bat """
     conda activate && python -m pytest -v -s --fulltrace -m "(not slow) and (not mgpu)" tests\\python-gpu
     """