Only available on M10+ clusters
Monitor collection-level query latency with Namespace Insights. The Namespace Insights page displays two charts and a table with information for each top or pinned namespace. The information includes metrics and statistics for certain hosts and operation types. You can manage pinned namespaces and choose up to five namespaces to show in the corresponding query latency charts.
Required Access
To view collection-level query latency with Namespace Insights, you must have Project Read Only
, Project Observability Viewer
, Project Data Access Read Only
, Project Data Access Read/Write
, or Project Data Access Admin
access to the project.
Considerations
The Namespace Insights tab is supported only for Atlas M10+ clusters.
If you have Queryable Encryption enabled for a collection, Namespace Insights doesn't display the collection in this location. Atlas redacts this information.
Atlas displays top namespaces by default. Depending on the time range, a namespace might fall in and out of the monitored list. Atlas interpolates missing data when at least one host metric exists in both ends of the time range. If Atlas encounters missing data, dotted lines connect the available data points.
If you reach the data limit for a page load, the following error message appears:
Chart data limit reached. Try a smaller time window or fewer hosts. The Namespace Insights tab doesn't support time series collections.
High-Latency $lookup Operations
Some high-latency $lookup
operations don't generate a slow query log for the foreign collection. This can occur because slow query logs correspond with operations that are reported in the Query Profiler, whereas latency metrics increment only when a collection lock is acquired.
If the $lookup
query on a shard can perform a local read, the $lookup
doesn't record a separate operation for querying the foreign collection. A local read refers to when the query on the foreign collection targets only the same shard where the current operation is being executed. As a result, the $lookup
operation increases the Namespace Insights latency metrics and operation counts, but does not generate a slow query log for the foreign collection.
Access Namespace Insights
To access Namespace Insights:
In Atlas, go to the Clusters page for your project.
Warning
Navigation Improvements In Progress
We're currently rolling out a new and improved navigation experience. If the following steps don't match your view in the Atlas UI, see the preview documentation.
If it's not already displayed, select the organization that contains your desired project from the Organizations menu in the navigation bar.
If it's not already displayed, select your desired project from the Projects menu in the navigation bar.
If it's not already displayed, click Clusters in the sidebar.
The Clusters page displays.
Filter Query Insights
You can filter the Query Insights page by node, node state (primary or secondary), and shard. You can also filter by a custom date range within the last seven days, or select one of the following preset time ranges:
7 days
5 days
2 days
24 hours (default)
12 hours
8 hours
1 hour
When you apply a filter, Atlas re-fetches data for the charts and table on the current screen.
Note
Analytics nodes are included when you filter by secondary node state.
View Metrics in Charts
The Namespace Insights page displays two charts that each visualize a selected metric for up to five selected namespaces over the filtered time range.
By default, Atlas charts metrics for pinned namespaces and top namespaces with the highest total latency. To choose which namespaces to chart, see Select Namespaces to Chart. To find and pin namespaces, see Manage Pinned Namespaces.
To select which metrics to visualize and filter by operation type:
Select the metrics to display.
Select one of the following metrics:
Metric | Description |
---|---|
Total latency | Rate that indicates the total combined server operation duration on a collection (total combined server operation duration / collection interval in seconds). |
Average latency | Difference between two server operation times, collected 10 minutes apart, divided by the difference between two total server operation count values collected over the same 10-minute interval. |
P50 latency | 50th percentile in the latency histogram. |
P95 latency | 95th percentile in the latency histogram. |
P99 latency | 99th percentile in the latency histogram. |
Operation count | Rate that indicates the total number of server operations performed on a collection (total server operations / collection interval) |
Manage Pinned Namespaces
You can search and pin a maximum of five namespaces to the top of the table from the Pinned Namespace dialog box or Search namespaces search box.
To manage pinned namespaces from the Pinned Namespace dialog box:
To manage pinned namespaces from the Search namespaces search box:
Select Namespaces to Chart
Atlas displays up to five namespaces. It displays pinned namespaces (if any) and then top namespaces with the highest total latency by default. You can also manually select the namespaces to chart.
To select namespaces:
Edit Columns
Atlas displays the following table columns by default for pinned namespaces (if any) and top namespaces:
Total latency for all operation types
Average latency for all operation types
P95 latency for all operation types
Operation Count for all operation types
To adjust the metric and operation type columns:
Go to a Collection
You can go to a collection in the Atlas UI from the table.
To go to a collection: