What are the top caching strategies?
Read data from the system:
🔹 Cache aside
🔹 Read through
Write data to the system:
🔹 Write around
🔹 Write back
🔹 Write through
The diagram below illustrates how those 5 strategies work. Some of the caching strategies can be used together.
I left out a lot of details as that will make the post very long. Feel free to leave a comment so we can learn from each other.
If you enjoyed this post, you might like our system design interview books as well.
**Write-through**: data is written in cache & DB; I/O completion is confirmed only when data is written in both places
**Write-around**: data is written in DB only; I/O completion is confirmed when data is written in DB
**Write-back**: data is written in cache first; I/O completion is confirmed when data is written in cache; data is written to DB asynchronously (background job) and does not block the request from being processed
What is the difference between write-around and cache-aside? They both seem very similar.