Remove MINIO_DEBUG environment variable (#2794)

Removes the unimplemented settings of MINIO_DEBUG=mem and makes
MINIO_DEBUG=lock the default behaviour.

cmd/globals.go

@@ -21,7 +21,6 @@ import (
 
 	"github.com/fatih/color"
 	"github.com/minio/minio/pkg/objcache"
-	"os"
 )
 
 // Global constants for Minio.
@@ -44,9 +43,6 @@ var (
 	globalQuiet = false // Quiet flag set via command line
 	globalTrace = false // Trace flag set via environment setting.
 
-	globalDebug       = false // Debug flag set to print debug info.
-	globalDebugLock   = false // Lock debug info set via environment variable MINIO_DEBUG=lock .
-	globalDebugMemory = false // Memory debug info set via environment variable MINIO_DEBUG=mem
 	// Add new global flags here.
 
 	// Maximum connections handled per
@@ -75,15 +71,3 @@ var (
 	colorBlue = color.New(color.FgBlue).SprintfFunc()
 	colorBold = color.New(color.Bold).SprintFunc()
 )
-
-// fetch from environment variables and set the global values related to locks.
-func setGlobalsDebugFromEnv() {
-	debugEnv := os.Getenv("MINIO_DEBUG")
-	switch debugEnv {
-	case "lock":
-		globalDebugLock = true
-	case "mem":
-		globalDebugMemory = true
-	}
-	globalDebug = globalDebugLock || globalDebugMemory
-}