AWS Lightsail Metric graphs "No data available"

Question

We're using AWS Lightsail PostgreSQL Database. We've been experiencing errors with our C# application timing out when using the connection to database. As I'm trying to debug the issue, I went to look at the Metric graphs in AWS. I noticed that many of the graphs have frequent gaps in the data, labeled No data available . See image below.

This graph (and most of the other metrics) shows frequent gaps in the data. I'm trying to understand if this is normal, or could be a symptom of the problem. If I go back to 2 weeks timescale, there does not appear to be any other strange behaviors in any of the metric data. For example, I do not see a point in time in the past where the CPU or memory usage went crazy. The issue started happening about a week ago, so I was hoping the metrics would have helped explained why the connections to the PostgreSQL database are failing from C#.

So I guess my question is, are those frequent gaps of No data available normal for a AWS Lightsail Postgres Database?

Other Data about the machine:

1 GB RAM, 1 vCPU, 40 GB SSD
PostgreSQL database (12.11)

In the last two weeks (the average metrics show):

• CPU utilization has never gone over 20%
• Database connections have never gone over 35 (usually less than 5) (actually, usually 0 )
• Disk queue depth never goes over 0.2
• Free storage space hovers around 36.5 GB
• Network receive throughput is mostly less than 1 kB/s (with one spike to 141kB/s )
• Network transmit throughput is mostly less than 11kB/s with all spikes less than 11.5kB/s

I would love to view the AWS logs, but they are a month old, and when trying to view them they are filled with checkpoint starting/complete logs. They start at one month ago and each page update only takes me 2 hours forward in time (and taking ~6 seconds to fetch the logs). This would require me to do ~360 page updates, and when trying, my auth timed out.

Answer 1

So we never figured out the reason why, but this seems like it was a problem with the AWS LightSail DB. We ended up using a snapshot to create a new clone of the DB, and wiring the C# servers to the new DB. The latency issues we were having disappeared and the metric graphs looked normal (without the strange gaps).

I wish we were able to figure out the root of the problem. ATM, we are just hoping the problem does not return.

When in doubt, clone everything!