Revert "Improve parallelism of testing jobs"

This reverts commit 134ac92b096b09bbd4abf7769b88953a87cdde0f.

Change-Id: I66e05bec1a6b1beda36e903ec6f207b95a4eb6d2
diff --git a/test-salt-formulas-pipeline.groovy b/test-salt-formulas-pipeline.groovy
index 1494aca..4422ca6 100644
--- a/test-salt-formulas-pipeline.groovy
+++ b/test-salt-formulas-pipeline.groovy
@@ -3,6 +3,7 @@
  *  DEFAULT_GIT_REF
  *  DEFAULT_GIT_URL
  *  CREDENTIALS_ID
+ *  KITCHEN_TESTS_PARALLEL
  */
 def common = new com.mirantis.mk.Common()
 def gerrit = new com.mirantis.mk.Gerrit()
@@ -15,6 +16,13 @@
   gerritRef = null
 }
 
+def parallelGroupSize
+try {
+  parallelGroupSize = Integer.valueOf(PARALLEL_GROUP_SIZE)
+} catch (MissingPropertyException e) {
+  parallelGroupSize = 8
+}
+
 def defaultGitRef, defaultGitUrl
 try {
   defaultGitRef = DEFAULT_GIT_REF
@@ -84,9 +92,15 @@
             common.infoMsg("CUSTOM_KITCHEN_ENVS not empty. Running with custom enviroments: ${kitchenEnvs}")
           }
           if (kitchenEnvs != null && kitchenEnvs != '') {
+            def acc = 0
             def kitchenTestRuns = [:]
             common.infoMsg("Found " + kitchenEnvs.size() + " environment(s)")
             for (int i = 0; i < kitchenEnvs.size(); i++) {
+              if (acc >= parallelGroupSize) {
+                parallel kitchenTestRuns
+                kitchenTestRuns = [:]
+                acc = 0
+              }
               def testEnv = kitchenEnvs[i]
               kitchenTestRuns[testEnv] = {
                 build job: "test-salt-formulas-env", parameters: [
@@ -98,8 +112,11 @@
                   [$class: 'StringParameterValue', name: 'SALT_VERSION', value: SALT_VERSION]
                 ]
               }
+              acc++;
             }
-            parallel kitchenTestRuns
+            if (acc != 0) {
+              parallel kitchenTestRuns
+            }
           } else {
             common.warningMsg(".kitchen.yml file not found, no kitchen tests triggered.")
           }