Not getting accurate read latency stats for MongoDB
General
Escalation
General
Escalation
Description
How to test
None
How to document
None
Attachments
3
Activity
Show:
Aaditya Dubey September 7, 2024 at 3:03 PM
Hi
We still haven't heard any news from you. So, I assume the issue no longer persists and will close the ticket. If you disagree, reply and create a follow-up with a new Jira report.
Aaditya Dubey December 12, 2023 at 10:57 AM
Hi ,
Please let us know the PMM version which is being used here?
Sanjay Mange September 14, 2023 at 9:46 AM
Hi @Nurlan Moldomurov, Yes, I checked with 0.39.0, but I'm still not receiving the correct latency.
Sanjay Mange September 14, 2023 at 9:31 AM
Hi
Nurlan Moldomurov September 13, 2023 at 12:14 PM
Hi , have you checked with the latest version of mongodb_exporter?
We are not receiving reliable latency statistics.
MongoDB version : 4.2
OS version: Ubuntu 18.04
MongoDB exporter version: release-0.1x
Running the MongoDB exporter on each node to collect the statistics.
When examining the MongoDB logs and the Grafana dashboard, we notice a significant difference in the statistics.
Here are some examples of scenarios we tested on our machine:
I've run a script that reads from one collection, and the log file indicates that it takes one query 3 seconds to complete. We ran the script for thirty minutes, however when we checked Grafana, the average read latency was 1 second for thirty minutes .
One more scenario We used a new collection and ran a different script. We saw from the logs that each query was taking 8 seconds to complete. We ran that script for 30 minutes and received the same results on Grafana, i.e. 1 second.
For reference i am attaching Grafana query :
1st scenario screenshot and query:
2nd scenario screenshot and query: