[pve-devel] [RFC cluster/common/widget-toolkit/manager 0/4] split node memory graph into usage types

[Folke Gleumes <f.gleumes@proxmox.com>]

The goal of this patchseries is to make it more intuitive to understand
the memory usage of an instance by splitting the memory usage graph
into 'Used', 'Buffer/Cache', 'ZFS Arc' and 'Free' instead of 'Total'
and 'RAM usage', displayed as different colored segments in a stacking
graph that adds up to the total memory. Previously, the zfs arc counted
towards the used memory, which could give a skewed perspective, since
there is no visual difference between almost all memory being used with
next to no arc or half of the memory used with a big arc.

Since there has already been a heated discussion on Bugzilla [0] on what
to display, I thought I would post this as an RFC before I finish up the
patchseries.

Another question would be if other places that display the memory usage
should also be split, i.e. the progress bar and gauge chart in the
cluster overview. Previously they included the zfs arc, with this series
the arc is not counted as used memory, since it technically can be freed
(with some caveats).

Unfortunately, there is a visual inconsistency with the way that missing
data is displayed in the new graph, since it seems impossible to display
missing data as a gap when using an area graph, which is possible and
the default in the line graph that is used throughout the rest of the
ui.

Note that applying this patch will currently reset your metrics, so
you'll have to wait a bit to see results.

[0] https://bugzilla.proxmox.com/show_bug.cgi?id=1454

cluster: Folke Gleumes (1):
  rrd: add free, buffer/cache and arc size to memory statistics

 src/pmxcfs/status.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

common: Folke Gleumes (1):
  add more detailed statistics to memory report

 src/PVE/ProcFSTools.pm | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

widget-toolkit: Folke Gleumes (1):
  add option to display rrd graph as stacking

 src/panel/RRDChart.js | 59 +++++++++++++++++++++++++++++++++----------
 1 file changed, 46 insertions(+), 13 deletions(-)

manager: Folke Gleumes (1):
  split ram usage into usage types

 PVE/API2/Nodes.pm            |  6 +++---
 PVE/API2Tools.pm             |  2 +-
 PVE/Service/pvestatd.pm      | 15 +++++++++++----
 www/manager6/node/Summary.js |  6 ++++--
 4 files changed, 19 insertions(+), 10 deletions(-)

-- 
2.39.2