Merge pull request #209840 from varun-dhawan/varun-azure-docs-pr

[Azure PG Flex] - updates restart recommendation for scaling resources

Author: prmerger-automator[bot]

articles/postgresql/flexible-server/concepts-compute-storage.md

@@ -173,7 +173,9 @@ After you create your server, you can independently change the vCores, the compu
 > [!NOTE]
 > The storage size can only be increased. You cannot go back to a smaller storage size after the increase.
 
-When you change the number of vCores or the compute tier, the server is restarted for the new server type to take effect. During the moment when the system switches over to the new server, no new connections can be established, and all uncommitted transactions are rolled back. This window varies, but in most cases, is less than a minute. Scaling the storage works the same way, and also requires a short restart.
+When you change the number of vCores or the compute tier, the server is restarted for the new server type to take effect. During the moment when the system switches over to the new server, no new connections can be established, and all uncommitted transactions are rolled back. The time it takes to restart your server depends on crash recovery process and database activity at the time of restart. Restart typically takes one minute or less, however can be higher and can take several minutes depending upon transactional activity at time of restart. Scaling the storage works the same way, and requires restart. 
+
+To improve the restart time, we recommend to perform scale operations during non-peak hours, that will reduce the time needed to restart the database server.
 
 Changing the backup retention period is an online operation.