read file size and number of samples for benchmark test from flags

The values default to what we used previously.

benchmark/benchmark_suite_test.go

@@ -1,6 +1,8 @@
 package benchmark
 
 import (
+	"flag"
+
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
 
@@ -11,3 +13,14 @@ func TestBenchmark(t *testing.T) {
 	RegisterFailHandler(Fail)
 	RunSpecs(t, "Benchmark Suite")
 }
+
+var (
+	size    int // file size in MB, will be read from flags
+	samples int // number of samples for Measure, will be read from flags
+)
+
+func init() {
+	flag.IntVar(&size, "size", 50, "data length (in MB)")
+	flag.IntVar(&samples, "samples", 6, "number of samples")
+	flag.Parse()
+}