Description of problem ====================== Memory Utilization chart doesn't follow usual conventions for reporting memory usage: * stacked area graph[1] is not used to convey the data * choice of different types of memory allocation reported in the chart looks weird (eg. both cache and slab reclaimable is reported, even though cache (usually) includes slab reclaimable memory as well) This makes this chart less convenient and harder to understand. [1] https://datavizcatalogue.com/methods/stacked_area_graph.html Version-Release number of selected component ============================================ tendrl-monitoring-integration-1.6.3-7.el7rhgs.noarch Steps to Reproduce ================== 1. Instal RHGS WA using tendrl-ansible 2. Import Trusted storage pool with at least one volume 3. Let RHGS WA to monitor cluster for some time 4. Go to Host dashboard and check Memory Utilization chart there Actual results ============== The chart report each type of memory allocation independently, plotting it as a line chart. This makes it hard to understand the data reported there. See screenshot 1. Expected results ================ The Memory Utilization panel uses tacked area graph (see screenshots with example of such charts). Values reported on the chart matches Red Hat recommendations about reporting memory usage. Additional info =============== Related to BZ 1614001 (Description of Memory Utilization panel on Host dashboard is misleading). Definition of stacked are graph: https://datavizcatalogue.com/methods/stacked_area_graph.html Why is stacked area graph preferred for reporting memory utilization: https://blog.serverdensity.com/how-to-design-useful-monitoring-graphs-and-visualizations/ See screenshot of google image search, looking for "memory utilization graph" images: all top results reports memory utilization using stacked are charts. This particular design of RHGS WA Memory Utilization charts has been discussed upstream here: https://github.com/Tendrl/monitoring-integration/issues/164 See also design wikipage of Cockpit project about fMemory graphs: https://github.com/cockpit-project/cockpit/wiki/Feature:-Memory-graphs
Created attachment 1475092 [details] screenshot 1: Memory Utilization chart on Host dashboard
Created attachment 1475094 [details] screenshot 2: munin memory chart for the same machine and time range, which uses stacked area graph
Created attachment 1475098 [details] google image search, looking for "memory utilization graph" images: all top results reports memory utilization using stacked are charts
I too agree the memory and CPU "trend" charts should be stacked. I don't recall the previous upstream issues on this, but I know there's lots of issues raised upstream how to do stacked charts in grafana and it not always working and depends on the grafana version and plug-in. That being said, I don't believe we can stack if with line charts (as stacked area charts like in Munin), but it looks like we can do this with the stacked bar charts in grafana. See http://docs.grafana-zabbix.org/guides/gettingstarted/ (do a find for "stacked bars" and it should be fairly straight forward to change this, and there might be some adjustments with regards to max data points to make it look better.) Thoughts? Similar to https://bugzilla.redhat.com/show_bug.cgi?id=1614877.