Query taking 10x longer

David_Walters · 2025-02-10T13:46:02.378Z

Since February 7th, I’ve noticed that when running a large query, the execution time has increased dramatically, becoming about 10 times longer.

The query is being called through C#, and there are only about 2500 records in total. Before February 7th, the query took around 3 seconds to complete, but now it takes over 30 seconds.

Interestingly, when I run the same query through MongoDB Compass, it executes quickly as expected. However, any query execution outside of MongoDB Compass (e.g., through my C# code) is taking around 30 seconds.

I can’t figure out what is causing this delay, as no code changes have been made recently.

Michael_Lynn · 2025-02-10T18:11:11.014Z

I’m curious… If you’re running Compass from your local computer, and the application is running from a server somewhere, I’m tempted to accuse the network. Can you verify the connectivity between your local, and your application nodes?

Try measuring connection time… something like:

var client = new MongoClient("your_connection_string");
stopwatch.Stop();
Console.WriteLine($"Connection Time: {stopwatch.ElapsedMilliseconds} ms");
`

David_Walters · 2025-02-11T07:39:33.198Z

When I run the query in compass it runs fast. When I use the same query is visual studio it now takes 30 seconds. Also when I run it from AWS lambda function it takes 30 seconds. This all started on the 7th