Flush All Memcached Data in C# (Detailed Guide w/ Code Examples)

Use Case(s)

When using Memcached for caching, there may be scenarios where you need to clear all data from the cache. This operation can be useful during:

• Development and testing phases where you want to ensure a clean starting point.
• Situations where the cache becomes inconsistent with the primary data store.
• Addressing issues caused by stale or corrupted cache entries.

Code Examples

C# has several libraries that provide interfaces to interact with Memcached, one of them being EnyimMemcached.

First, install it through NuGet package manager:

Install-Package EnyimMemcached

Here's how to flush all data from Memcached using this library:

using Enyim.Caching;

// Create a new MemcachedClient instance
MemcachedClient client = new MemcachedClient();

// Flush all data
client.FlushAll();

The FlushAll function sends a flush command to the Memcached server, instructing it to clear all data.

Best Practices

• Use the FlushAll operation sparingly as it clears all data from the entire cache, which could impact performance if the cache has to be repopulated from the database.
• Use appropriate logging when performing a FlushAll operation to help in debugging and tracing potential issues.
• Consider using a per-key expiration strategy as an alternative to flushing the entire cache, where possible.

Common Mistakes

• Running FlushAll during peak traffic times: As this operation is quite disruptive, try to schedule such operations during off-peak hours.
• Frequent use of FlushAll: If you find yourself frequently needing to flush the cache, it may indicate a problem with how data is being cached or invalidated.

FAQs

Q: Will the FlushAll command remove all items from all servers in a Memcached cluster?

A: Yes, the FlushAll command will remove all items from all servers in a Memcached cluster.

Q: Can I restore the items after running a FlushAll command?

A: No, once items are removed from the cache using FlushAll, they cannot be restored.