platform: Improve iOS OOM killer

experimental/libbox/memory.go

@@ -4,20 +4,23 @@ import (
 	"math"
 	runtimeDebug "runtime/debug"
 
-	"github.com/sagernet/sing-box/common/conntrack"
+	C "github.com/sagernet/sing-box/constant"
 )
 
+var memoryLimitEnabled bool
+
 func SetMemoryLimit(enabled bool) {
-	const memoryLimit = 45 * 1024 * 1024
-	const memoryLimitGo = memoryLimit / 1.5
+	memoryLimitEnabled = enabled
+	const memoryLimitGo = 45 * 1024 * 1024
 	if enabled {
 		runtimeDebug.SetGCPercent(10)
-		runtimeDebug.SetMemoryLimit(memoryLimitGo)
-		conntrack.KillerEnabled = true
-		conntrack.MemoryLimit = memoryLimit
+		if C.IsIos {
+			runtimeDebug.SetMemoryLimit(memoryLimitGo)
+		}
 	} else {
 		runtimeDebug.SetGCPercent(100)
-		runtimeDebug.SetMemoryLimit(math.MaxInt64)
-		conntrack.KillerEnabled = false
+		if C.IsIos {
+			runtimeDebug.SetMemoryLimit(math.MaxInt64)
+		}
 	}
 }