Write-Behind / Write-Back

Acknowledge buffered writes before persistence only when durability, ordering, replay, and recovery are acceptable.

About 20 minAdvancedReviewed Aug 2026Progress unavailableRead to the end

What you will learn

Acknowledge buffered writes before persistence only when durability, ordering, replay, and recovery are acceptable.

Acknowledge before durable persistence#

Write-behind, also called write-back, updates a cache or buffer and persists to the backing store asynchronously. It can batch many high-volume counter changes and reduce source writes.

Conceptual write-behind flow

The cache acknowledges an application update first, then persists the buffered or batched change to the database later.

Advantage	Risk introduced
Low acknowledgement latency	Data loss before persistence
Write coalescing and batches	Ordering and retry complexity
Lower backing-store write load	Shutdown, replay, and recovery work

Worked example

Aggregate view counters

One million page views do not always require one million immediate durable counter writes. A cache can accumulate increments and flush batches. The product must accept bounded loss or provide a durable log and idempotent replay.

Apply the lesson

What you will learn

Acknowledge buffered writes before persistence only when durability, ordering, replay, and recovery are acceptable.

Acknowledge before durable persistence#

Write-behind, also called write-back, updates a cache or buffer and persists to the backing store asynchronously. It can batch many high-volume counter changes and reduce source writes.

Conceptual write-behind flow

The cache acknowledges an application update first, then persists the buffered or batched change to the database later.

Advantage	Risk introduced
Low acknowledgement latency	Data loss before persistence
Write coalescing and batches	Ordering and retry complexity
Lower backing-store write load	Shutdown, replay, and recovery work

Worked example

Aggregate view counters

Apply the lesson

Write-Behind / Write-Back

What you will learn

Acknowledge before durable persistence#

Aggregate view counters

Related practice problems

Finish this lesson

Write-Behind / Write-Back

What you will learn

Acknowledge before durable persistence#

Aggregate view counters

Related practice problems

Finish this lesson