etcdctl/check: create new check command for memory usage

Create a new command similar to check perf that can check the memory
consumption for putting different workloads. Return user with a message
that whether there are enough memory for a given workload with pass
or fail.

Fixed etcd-io#9121

etcdctl/ctlv3/command/check.go

@@ -338,12 +338,8 @@ func newCheckDatascaleCommand(cmd *cobra.Command, args []string) {
  r := report.NewReport("%4.4f")
  var wg sync.WaitGroup
 
- var statsBefore runtime.MemStats
- runtime.ReadMemStats(&statsBefore)
- totalOSMemory := statsBefore.Sys
- totalAllocBefore := statsBefore.Alloc
  wg.Add(len(clients))
- fmt.Println(fmt.Sprintf("Start data scale check for work load [%v key-value pairs, %vkb per key-value, %v concurrent clients].", cfg.limit, cfg.kvSize, cfg.clients))
+ fmt.Println(fmt.Sprintf("Start data scale check for work load [%v key-value pairs, %v bytes per key-value, %v concurrent clients].", cfg.limit, cfg.kvSize, cfg.clients))
  for i := range clients {
  go func(c *v3.Client) {
  defer wg.Done()
@@ -368,13 +364,13 @@ func newCheckDatascaleCommand(cmd *cobra.Command, args []string) {
  close(r.Results())
  s := <-sc
 
- // check memory consumption
- var statsAfter runtime.MemStats
- runtime.ReadMemStats(&statsAfter)
- totalAllocAfter := statsAfter.Alloc
- diffAlloc := totalAllocAfter - totalAllocBefore
+ // check memory consumption statistics
+ var stats runtime.MemStats
+ runtime.ReadMemStats(&stats)
+ totalAllocMemory := stats.Alloc
+ totalOSMemory := stats.Sys
  // rounded percent of memory consumed
- percentAlloc := float64((diffAlloc * 100) / totalOSMemory)
+ percentAlloc := float64((totalAllocMemory * 100) / totalOSMemory)
 
  ctx, cancel = context.WithCancel(context.Background())
  _, err = clients[0].Delete(ctx, checkDatascalePrefix, v3.WithPrefix())
@@ -392,7 +388,7 @@ func newCheckDatascaleCommand(cmd *cobra.Command, args []string) {
  ok = false
  }
 
- mbUsed := float64(diffAlloc / (1024 * 1024))
+ mbUsed := float64(totalAllocMemory / (1024 * 1024))
  mbTotal := float64(totalOSMemory / (1024 * 1024))
 
  if int(percentAlloc) > 60 { // leaves less than 40 percent of memory
@@ -401,7 +397,7 @@ func newCheckDatascaleCommand(cmd *cobra.Command, args []string) {
  } else {
  fmt.Println(fmt.Sprintf("PASS: Memory usage is %v%% of available. Expected less than %v%%.", int(percentAlloc), 60))
  }
- fmt.Println(fmt.Sprintf("INFO: Approx total process memory used : %vmb out of %vmb.", int(mbUsed), int(mbTotal)))
+ fmt.Println(fmt.Sprintf("INFO: Approximate total process memory used : %vmb out of %vmb.", int(mbUsed), int(mbTotal)))
  if ok {
  fmt.Println("PASS")
  } else {