Scaling (Preview)

If you determine that your cache is no longer meeting the requirements of your application, you can change to a larger or smaller cache pricing tier that is right for your application. For more information on determining which cache pricing tier is right for you, see What Redis Cache offering and size should I use.

One of the top asks from customers on the Cache User Voice Site is to have the ability to scale up a pricing plan for Redis Cache. The below screen shot shows how you can scale up or down a cache created in a Standard tier. To learn more about How to Scale Azure Redis Cache, read https://azure.microsoft.com/en-us/documentation/articles/cache-how-to-scale/

We are releasing this feature to elicit feedback. Based on the feedback we receive, we will release this feature to General Availability soon.

New Configuration Settings

You can now configure the following settings in Redis.

Key Space Notifications

Redis provides a way for clients to receive events affecting the keys. This feature is called Redis Keyspace Notifications and you can read more about it on the Redis website.

This was also a highly requested feature on the Azure Redis Cache User voice site: Support Redis Expire Keyspace Notifications

For more information, see Redis Keyspace Notifications and for sample code, see the KeySpaceNotifications.cs file in the Hello world sample.

Maxmemory-reserved

The maxmemory-reserved setting configures the amount of memory in MB that is reserved for non-cache operations such as replication during failover. It can also be used when you have a high fragmentation ratio for your Redis Cache. Setting this value allows you to have a more consistent Redis server experience when your load varies. This value should be set higher for workloads which are write heavy. When memory is reserved for such operations it is unavailable for storage of cached data.

For more information read How to Monitor Azure Redis Cache

Redis Server Load counter

This counter allows you to measure how busy Redis server is. This counter shows you the percentage of cycles in which the Redis server is busy processing and not waiting idle for messages. If this counter reaches 100 it means the Redis server has hit a performance ceiling and the CPU can’t process work any faster. If you are seeing high Redis Server Load then you will see timeout exceptions in the client.

In this case you should consider scaling up or partitioning your data into multiple caches. The below screen shot shows the Redis Server Load:

Open sourcing ASP.NET Session & Output Cache providers for Redis

The ASP.NET Session and Output Cache providers for Redis were recently open sourced and the code was made available on GitHub at https://github.com/Azure/aspnet-redis-providers . You can send PRs or open issues for the providers in the mentioned repo.

Summary

The Azure Redis Cache team hopes that you find these feature useful. Please try it out and give us feedback on Azure Cache Forum or StackOverflow for Azure Redis Cache.