Less racey logic for resource usage

environment/docker/stats.go

@@ -61,7 +61,7 @@ func (e *Environment) pollResources(ctx context.Context) error {
 				atomic.AddUint64(&tx, nw.RxBytes)
 			}
 
-			st := &environment.Stats{
+			st := environment.Stats{
 				Memory:      calculateDockerMemory(v.MemoryStats),
 				MemoryLimit: v.MemoryStats.Limit,
 				CpuAbsolute: calculateDockerAbsoluteCpu(&v.PreCPUStats, &v.CPUStats),

environment/stats.go

@@ -1,13 +1,9 @@
 package environment
 
-import "sync"
-
 // Defines the current resource usage for a given server instance. If a server is offline you
 // should obviously expect memory and CPU usage to be 0. However, disk will always be returned
 // since that is not dependent on the server being running to collect that data.
 type Stats struct {
-	mu sync.RWMutex
-
 	// The total amount of memory, in bytes, that this server instance is consuming. This is
 	// calculated slightly differently than just using the raw Memory field that the stats
 	// return from the container, so please check the code setting this value for how that
@@ -33,15 +29,3 @@ type Stats struct {
 		TxBytes uint64 `json:"tx_bytes"`
 	} `json:"network"`
 }
-
-// Resets the usages values to zero, used when a server is stopped to ensure we don't hold
-// onto any values incorrectly.
-func (s *Stats) Empty() {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-
-	s.Memory = 0
-	s.CpuAbsolute = 0
-	s.Network.TxBytes = 0
-	s.Network.RxBytes = 0
-}