Merge pull request #383 from avenga/refine-ulimits

Simplify/reduce ulimit info to file descriptors

CHANGELOG.md

@@ -7,7 +7,7 @@ Unreleased changes are available as `avenga/couper:edge` container.
 * **Added**
   * Register `default` function as `coalesce` alias ([#356](https://github.com/avenga/couper/pull/356))
   * New HCL function [`relative_url()`](./docs/REFERENCE.md#functions) ([#361](https://github.com/avenga/couper/pull/361))
-  * Log system resource limits at startup ([#334](https://github.com/avenga/couper/pull/334))
+  * Log file descriptor limit at startup ([#383](https://github.com/avenga/couper/pull/383))
 
 * **Changed**
   * [`server` block](./docs/REFERENCE.md#server-block) label is now optional, [`api` block](./docs/REFERENCE.md#api-block) may be labelled ([#358](https://github.com/avenga/couper/pull/358))

command/run.go

@@ -88,28 +88,14 @@ func (a AcceptForwardedValue) Set(s string) error {
 }
 
 func (r *Run) Execute(args Args, config *config.Couper, logEntry *logrus.Entry) error {
-	rlimits := map[string]int{
-		"RLIMIT CPU":    syscall.RLIMIT_CPU,
-		"RLIMIT Data":   syscall.RLIMIT_DATA,
-		"RLIMIT CORE":   syscall.RLIMIT_CORE,
-		"RLIMIT AS":     syscall.RLIMIT_AS,
-		"RLIMIT Stack":  syscall.RLIMIT_STACK,
-		"RLIMIT FSIZE":  syscall.RLIMIT_FSIZE,
-		"RLIMIT Nofile": syscall.RLIMIT_NOFILE,
-	}
-	for key, value := range rlimits {
-		lim := syscall.Rlimit{}
-		err := syscall.Getrlimit(value, &lim)
-		if err != nil {
-			logEntry.Infof("an error occured while retrieving '%s'", key)
-			continue
-		}
-		if lim.Cur < 4096 {
-			logEntry.Warnf("%s Current: %d, %s Max: %d", key, lim.Cur, key, lim.Max)
-			continue
-		}
-		logEntry.Infof("%s Current: %d, %s Max: %d", key, lim.Cur, key, lim.Max)
+	lim := syscall.Rlimit{}
+	err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim)
+	if err != nil {
+		logEntry.Warnf("ulimit: error retrieving file descriptor limit")
+	} else {
+		logEntry.Infof("ulimit: max open files: %d (hard limit: %d)", lim.Cur, lim.Max)
 	}
+
 	r.settingsMu.Lock()
 	*r.settings = *config.Settings
 	r.settingsMu.Unlock()
@@ -131,7 +117,7 @@ func (r *Run) Execute(args Args, config *config.Couper, logEntry *logrus.Entry)
 
 	// Some remapping due to flag set pre-definition
 	env.Decode(r.settings)
-	err := r.settings.SetAcceptForwarded()
+	err = r.settings.SetAcceptForwarded()
 	if err != nil {
 		return err
 	}