Atlas provides several tools to help analyze slow queries executed on your clusters. See the following sections for descriptions of each tool. To optimize your query performance, review the best practices for query performance.
Performance Advisor
The Performance Advisor monitors queries that MongoDB considers slow and suggests new indexes to improve query performance.
You can use the Performance Advisor to review the following information:
Query Insights
The following tools are found in the Query Insights tab:
Query Shape Insights
Query Shape Insights displays performance statistics for query shapes with slow-running queries. You can select up to five query shapes to view their metrics in charts, and filter by host, shard, and time range to monitor the most relevant performance metrics and statistics for your project.
Namespace Insights
Namespace Insights displays query latency statistics for collections with slow-running queries. You can pin up to five namespaces to view their metrics in charts, and filter by host, shard, time range, and operation type to monitor the most relevant latency metrics and statistics for your project.
Query Profiler
The Query Profiler displays slow-running operations and their key performance statistics. You can explore a sample of historical queries for up to the last seven days without additional cost or performance overhead. Before you enable the Query Profiler, see Considerations.
Real-Time Performance Panel (RTPP)
The Real-Time Performance Panel identifies relevant database operations, evaluates query execution times, and shows the ratio of documents scanned to documents returned during query execution. RTPP is enabled by default.
Important
Required Privileges
To enable or disable Real-Time Performance Panel for a
project, you must have the Project Owner role for the
project.
Best Practices for Query Performance
To optimize query performance, review the following best practices:
Create queries that your current indexes support to reduce the time needed to search for your results.
Avoid creating documents with large array fields that require a lot of processing to search and index.
Optimize your indexes and remove unused or inefficent indexes. Too many indexes can negatively impact write performance.
Consider the suggested indexes from the Performance Advisor with the highest Impact scores and lowest Average Query Targeting scores.
Create the indexes that the Performance Advisor suggests when they align with your Indexing Strategies.
The Performance Advisor cannot suggest indexes for MongoDB databases configured to use the ctime timestamp format. As a workaround, set the timestamp format for such databases to either iso8601-utc or iso8601-local.
Perform rolling index builds to reduce the performance impact of building indexes on replica sets and sharded clusters.
Drop unused, redundant, and hidden indexes to improve write performance and free storage space.