You need to disable it in libs/poolWorker.js by modifying code.

Add in config.js new variable

...
    "switchingEnable": false,
    "switching": {
...

Modify code:

--- a/poolWorker.js
+++ b/poolWorker.js.new
@@ -18,7 +18,9 @@ module.exports = function(logger){

     var proxySwitch = {};

-    var redisClient = redis.createClient(portalConfig.redis.port, portalConfig.redis.host);
+    if (portalConfig.switchingEnable) {
+        var redisClient = redis.createClient(portalConfig.redis.port, portalConfig.redis.host);
+    }

     //Handle messages from master process sent via IPC
     process.on('message', function(message) {
@@ -45,6 +47,7 @@ module.exports = function(logger){

             // IPC message for pool switching
             case 'coinswitch':
+                if (portalConfig.switchingEnable) {
                 var logSystem = 'Proxy';
                 var logComponent = 'Switch';
                 var logSubCat = 'Thread ' + (parseInt(forkId) + 1);
@@ -89,6 +92,9 @@ module.exports = function(logger){
                     });

                 }
+                } else {
+                    logger.error(logSystem, logComponent, logSubCat, 'Switch message can not be handled: no coin switches is configured');
+                }
                 break;
         }
     });
@@ -215,7 +226,7 @@ module.exports = function(logger){
     });


-    if (portalConfig.switching) {
+    if (portalConfig.switchingEnable) {

         var logSystem = 'Switching';
         var logComponent = 'Setup';
@@ -311,6 +322,7 @@ module.exports = function(logger){

         logger.debug(logSystem, logComponent, algo, 'Setting proxy difficulties after pool start');

+        if (portalConfig.switchingEnable) {
         Object.keys(portalConfig.switching).forEach(function(switchName) {
             if (!portalConfig.switching[switchName].enabled) return;

@@ -331,5 +343,6 @@ module.exports = function(logger){
                 }
             }
         });
+        }
     };
 };