metrics: Add env files for FIO

This PR adds the env files for FIO for kata metrics.

Signed-off-by: Gabriela Cervantes <gabriela.cervantes.tellez@intel.com>

tests/metrics/storage/fio-k8s/pkg/env/Makefile

@@ -0,0 +1,9 @@
+#
+# Copyright (c) 2021 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+gomod:
+	 GO111MODULE=on go mod edit -replace=github.com/kata-containers/tests/metrics/exec=../exec
+	 GO111MODULE=on go mod tidy

tests/metrics/storage/fio-k8s/pkg/env/env.go

@@ -0,0 +1,39 @@
+// Copyright (c) 2021 Intel Corporation
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+package env
+
+import (
+	exec "github.com/kata-containers/tests/metrics/exec"
+)
+
+//logger interface for pkg
+var log logger
+var Debug bool = false
+
+type logger interface {
+	Infof(string, ...interface{})
+	Debugf(string, ...interface{})
+	Errorf(string, ...interface{})
+}
+
+func SetLogger(l logger) {
+	log = l
+}
+
+var sysDropCachesPath = "/proc/sys/vm/drop_caches"
+
+func DropCaches() (err error) {
+	log.Infof("drop caches")
+	_, err = exec.ExecCmd("sync", Debug)
+	if err != nil {
+		return err
+	}
+
+	_, err = exec.ExecCmd("echo 3 | sudo tee "+sysDropCachesPath, Debug)
+	if err != nil {
+		return err
+	}
+	return nil
+}