Query for Percent Memory Used

roopesh_shetty 

There is an example on the logs home page

It does have CPU info as well, but if you edit that out you have:

// Memory usage
// Chart all computers' used memory  over the last hour
Perf
| where TimeGenerated > ago(1h)
| where  CounterName == "% Used Memory" 
| project TimeGenerated, CounterName, CounterValue 
| summarize avg(CounterValue) by CounterName, bin(TimeGenerated, 1m)
| render timechart

Note: you have to collect "% Used Memory"  in log Analytics https://docs.microsoft.com/en-us/azure/azure-monitor/platform/data-sources-performance-counters