Average Memory Usage Query - Prometheus

Answer :

average memory usage for instances over the past 24 hours

You can use avg_over_time:

100 * (1 - ((avg_over_time(node_memory_MemFree[24h]) + avg_over_time(node_memory_Cached[24h]) + avg_over_time(node_memory_Buffers[24h])) / avg_over_time(node_memory_MemTotal[24h]))) 

For CPU, I was able to use irate

irate only looks at the last two samples, and that query is the inverse of how many modes you have and will be constant (it's always 0.1 on my kernel). You want

100 - (avg by (instance) (rate(node_cpu{job="node",mode="idle"}[5m])) * 100) 

Note that this is a 5 minute moving average and you can change [5m] to whatever period of time you are looking for such as [24h].

Update commands

CPU Usage :

(1 - avg(irate(node_cpu_seconds_total{mode="idle"}[10m])) by (instance)) * 100 

Memory Usage :

100 * (1 - ((avg_over_time(node_memory_MemFree_bytes[10m]) + avg_over_time(node_memory_Cached_bytes[10m]) + avg_over_time(node_memory_Buffers_bytes[10m])) / avg_over_time(node_memory_MemTotal_bytes[10m])))