Merge pull request #3041 from fjl/build-less-parallel

build: limit test concurrency

.travis.yml

@@ -3,9 +3,6 @@ go_import_path: github.com/ethereum/go-ethereum
 sudo: false
 matrix:
   include:
-    - os: linux
-      dist: trusty
-      go: 1.4.2
     - os: linux
       dist: trusty
       go: 1.5.4

build/ci.go

@@ -227,6 +227,9 @@ func doTest(cmdline []string) {
 
 	// Run the actual tests.
 	gotest := goTool("test")
+	// Test a single package at a time. CI builders are slow
+	// and some tests run into timeouts under load.
+	gotest.Args = append(gotest.Args, "-p", "1")
 	if *coverage {
 		gotest.Args = append(gotest.Args, "-covermode=atomic", "-cover")
 	}