Add notes on Debugging Data Corruption Issues

Author: mythz

README.md

@@ -761,6 +761,30 @@ daysOfWeek.PrintDump(); //[Sunday, Monday, Tuesday, ...]
 More examples can be found in the [Redis Eval Lua tests](https://github.com/ServiceStack/ServiceStack.Redis/blob/master/tests/ServiceStack.Redis.Tests/RedisClientEvalTests.cs
 )
 
+### Debugging Data Corruption Issues
+
+An issue that can be hard to debug is if the same `RedisClient` instance is shared across multiple threads which can result in returning corrupted data. 
+Typically this is a result of using `IRedisClient` field in a singleton instance or sharing it as a static instance. To prevent this, each Thread that
+uses Redis should retrieve the redis client within a using statement, e.g:
+
+```csharp
+using (var redis = redisManager.GetClient())
+{
+    //..         
+}
+```
+
+Unfortunately the call-site which returns the corrupted response or runtime Exception doesn't identify where else the Redis client instance was being used.
+To help identify where client instances are being used you can assert that the client is only used in the Thread that resolved it from the pool with:
+
+```csharp
+RedisConfig.AssertAccessOnlyOnSameThread = true;
+```
+
+This captures the Thread's StackTrace each time the client is resolved from the pool which as it adds a lot of overhead, should only be enabled when debugging connection issues. 
+
+If it does detect the client is being accessed from a different thread it will throw a `InvalidAccessException` with the message containing the different **Thread Ids** and the **original StackTrace** where the client was resolved from the pool. You can compare this with the StackTrace of the Exception to hopefully identify where the client is being improperly used.
+
 ## Copying
 
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