Review Asynchronous Replication performance

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This document describes how to view performance metrics for Asynchronous Replication.

To learn more about Asynchronous Replication, see About Asynchronous Replication .

Metrics

You can view the following Asynchronous Replication metrics in Cloud Monitoring :

Metric	Description
Async replication sent bytes count (disk/async_replication/sent_bytes_count)	The delta number of bytes sent through the cross-region network.
Async replication time since last replication (disk/async_replication/time_since_last_replication)	The number of seconds since the last replication was done, also known as the recovery point objective (RPO).

Monitor sent byte counts

Use the Async replication sent bytes countmetric to graph the average number of byte sent, sampled every minute. The number of sent bytes represents the data your workload writes to block storage, which affects the speed of replication.

1. In the Google Cloud console, go to the Cloud Monitoring  > Metrics Explorerpage.

   Go to the Metrics Explorer page

2. In the Select a metricsection, click the Metricmenu.

3. Select Disk( disk ).

4. Select the Diskactive metric category list, and then select Async replication sent bytes count( disk/async_replication/sent_bytes_count ).

5. Click Apply.

6. In the Transformmenu, select one of the following:

   • To view the total number of sent bytes, select None.
   • To view the number of bytes sent per second, select Rate.

7. In the Filterssection, do the following:

   1. Click Add filter.
   2. Click inside the Labelbox to view the list of available labels. Under the heading Resource labels, select project_id. Leave the Comparisonvalue set to = (equals) . In the Valuefield, type or select your project ID. Click Done.
   3. Click Add filter.
   4. In the Labelbox, select disk_id. Leave the Comparisonvalue set to = (equals) . In the Valuefield, type or select the ID of the primary disk that is replicating.
   5. Click Done.

8. Click More options.

9. In the Alignment functionmenu select an alignment function. The Meanalignment function shows the average number of bytes sent per minute, while the Maxalignment function shows the highest number of bytes sent per minute.

10. In the Min alignment periodmenu, select an alignment period. The alignment period must be at least one minute.

Monitor RPO

Use the Async replication time since last replicationmetric to graph the number of seconds since the last replication was done (RPO).

1. In the Google Cloud console, go to the Cloud Monitoring  > Metrics Explorerpage.

   Go to the Metrics Explorer page

2. On the Metrics Explorerpage, click Add query.

3. In the Select a metricsection, click the Metricmenu.

4. Select Disk( disk ).

5. Select the Diskactive metric category list, and then select Async replication time since last replication( disk/async_replication/time_since_last_replication ).

6. Click Apply.

7. In the Filterssection, add filters for your project ID and disk ID:

   1. Click Add filter.
   2. Click inside the Labelbox to view the list of available labels. Under the heading Resource labels, select project_id. Leave the Comparisonvalue set to = (equals) . In the Valuefield, type or select your project ID. Click Done.
   3. Click Add filter.
   4. In the Labelbox, select disk_id. Leave the Comparisonvalue set to = (equals) . In the Valuefield, type or select the ID of the primary disk that is replicating.
   5. Click Done.

8. Click More options.

9. In the Alignment functionmenu, select an alignment function. The Meanalignment function shows the average number of seconds since the last replication was done , while the Maxalignment function shows the highest number of seconds since the last replication was done .

10. In the Min alignment periodmenu, select the select an alignment period. The alignment period must be at least one minute.

11. Optional: Save the chart.

What's next

• Learn how to customize Asynchronous Replication chats with Metrics Explorer .
• Learn more about Asynchronous Replication .