Linux Harvester Memory Utilization Errors in System Status

Products

• CA Network Flow Analysis (NetQos / NFA)

Issue/Introduction

When looking at the Admin->System Status page of NFA, I am seeing Memory utilization warnings for my harvester showing about 98% utilized.

However when looking at the output of the "top" or "free -hm" command, it shows much more memory available then what the Watchdog Service reports in NFA.

 

Cause

The Netqos ReporterAnalyzer Watchdog service is using the "free" column from the output of the "top" or "free" commands to calculate the memory utilization.

For example below you see only 213M for the free column, but 4.6G showing as available.

# free -hm
              total        used        free      shared  buff/cache   available
Mem:     7.8G        2.3G     213M       327M           5.3G         4.6G
Swap:    7.9G        861M      7.0G

The "free" column doesn't take into account the memory in buff/cache, which is actually available to the OS to allocate dynamically, which means that the free column is not a good indicator of a memory utilization problem.

We have opened an internal defect, DE416030, to address this.
 

Environment

NFA with Linux Harvesters

Resolution

As a workaround you can follow the steps below to disable memory utilization warnings in the System Status page.

1. Go to the Admin->Watchdog Settings page in NFA.

2. Chang the Memory Utilization field from the default value of 80 to 100.

3. Click "Save".

4. Go back to the Admin->System Status page and the memory error should clear.