+ config: add "rlimit_nofile" setting - Maximum number of opened fd's per process

app.go

@@ -92,6 +92,11 @@ func run(args options) {
 		log.Fatal(err)
 	}
 
+	if (runtime.GOOS == "linux" || runtime.GOOS == "darwin") &&
+		config.RlimitNoFile != 0 {
+		setRlimit(config.RlimitNoFile)
+	}
+
 	// override bind host/port from the console
 	if args.bindHost != "" {
 		config.BindHost = args.bindHost
@@ -285,6 +290,18 @@ func enableTLS13() {
 	}
 }
 
+// Set user-specified limit of how many fd's we can use
+// https://github.com/AdguardTeam/AdGuardHome/issues/659
+func setRlimit(val uint) {
+	var rlim syscall.Rlimit
+	rlim.Max = uint64(val)
+	rlim.Cur = uint64(val)
+	err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rlim)
+	if err != nil {
+		log.Error("Setrlimit() failed: %v", err)
+	}
+}
+
 func cleanup() {
 	log.Info("Stopping AdGuard Home")
 

config.go

@@ -39,6 +39,8 @@ type configuration struct {
 	AuthName     string `yaml:"auth_name"`     // AuthName is the basic auth username
 	AuthPass     string `yaml:"auth_pass"`     // AuthPass is the basic auth password
 	Language     string `yaml:"language"`      // two-letter ISO 639-1 language code
+	RlimitNoFile uint   `yaml:"rlimit_nofile"` // Maximum number of opened fd's per process (0: default)
+
 	DNS       dnsConfig          `yaml:"dns"`
 	TLS       tlsConfig          `yaml:"tls"`
 	Filters   []filter           `yaml:"filters"`