Suggest an editImprove this articleRefine the answer for “How does synchronous replication differ from asynchronous replication?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Synchronous** and **asynchronous** replication differ in *when* changes on the primary server (master) count as successfully applied - before or after they're written to the replica: with synchronous replication the master **waits for confirmation** from the replica, while with asynchronous replication the transaction finishes right after being written to the master, and the replica catches up with a small delay. **Key point:** synchronous = safer but slower (guarantees full data consistency, used where integrity matters most - banking, finance); asynchronous = faster, suited to high-traffic systems, but the most recent changes can be lost if the master fails.Shown above the full answer for quick recall.Answer (EN)Image**Synchronous** and **asynchronous** replication differ in *when* changes on the primary server (master) count as successfully applied - before or after they're written to the replica. ### 1. Synchronous replication The master **waits for confirmation** from the replica that the data was written. - The transaction counts as complete only after both sides have it. - It guarantees **full data consistency**, the master and replica are always in sync. - The downside is it's **slower**, since it has to wait for the replica to respond. - It's used where data integrity matters most (banking, finance). ### 2. Asynchronous replication The master **doesn't wait** for confirmation from the replica. - The transaction completes right after being written to the master. - The replica catches up with a small delay (usually milliseconds to seconds). - The upside is it's **faster**, suited to high-traffic systems. - The downside is that recent changes can be lost if the master fails. **Summary:** Synchronous = safer, but slower. Asynchronous = faster, but with a risk of the copies diverging.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.