[pve-devel] [PATCH cluster v2 4/4] rrd: adapt to new RRD format with different aggregation windows

[Aaron Lauterer]

With PVE9 we introduced a new RRD format that has different aggregation
steps, similar to what we use in the Backup Server.
We therefore need to adapt the functions that get data from RRD
accordingly.

The result is usually a finer resolution for time windows larger than
hourly.
We also introduce decade as a time window. In case existing RRD files
have not yet been converted to the new RRD format, we need keep using
the old time windows. Additionally, since they only store data up to a
year, we catch the situation where a full decade might be requested and
pin it to a year.

Signed-off-by: Aaron Lauterer <a.lauterer at proxmox.com>
---
 src/PVE/RRD.pm | 52 ++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 42 insertions(+), 10 deletions(-)

diff --git a/src/PVE/RRD.pm b/src/PVE/RRD.pm
index 93df608..c95f495 100644
--- a/src/PVE/RRD.pm
+++ b/src/PVE/RRD.pm
@@ -14,14 +14,30 @@ sub create_rrd_data {
 
     my $rrd = "$rrddir/$rrdname";
 
+    # Format: [ resolution, number of data points/count]
+    # Old ranges, pre PVE9
+    my $setup_pve2 = {
+        hour => [60, 60], # 1 min resolution, one hour
+        day => [60 * 30, 70], # 30 min resolution, one day
+        week => [60 * 180, 70], # 3 hour resolution, one week
+        month => [60 * 720, 70], # 12 hour resolution, 1 month
+        year => [60 * 10080, 70], # 7 day resolution, 1 year
+    };
+
     my $setup = {
-        hour => [60, 70],
-        day => [60 * 30, 70],
-        week => [60 * 180, 70],
-        month => [60 * 720, 70],
-        year => [60 * 10080, 70],
+        hour => [60, 60], # 1 min resolution
+        day => [60, 1440], # 1 min resolution, full day
+        week => [60 * 30, 336], # 30 min resolution, 7 days
+        month => [3600 * 6, 121], # 6 hour resolution, 30 days, need one more count. Otherwise RRD gets wrong $step
+        year => [3600 * 6, 1140], # 6 hour resolution, 360 days
+        decade => [86400 * 7, 570], # 1 week resolution, 10 years
     };
 
+    if ($rrdname =~ /^pve2/) {
+        $setup = $setup_pve2;
+        $timeframe = "year" if $timeframe eq "decade"; # we only store up to one year in the old format
+    }
+
     my ($reso, $count) = @{ $setup->{$timeframe} };
     my $ctime = $reso * int(time() / $reso);
     my $req_start = $ctime - $reso * $count;
@@ -82,14 +98,30 @@ sub create_rrd_graph {
 
     my $filename = "${rrd}_${ds_txt}.png";
 
+    # Format: [ resolution, number of data points/count]
+    # Old ranges, pre PVE9
+    my $setup_pve2 = {
+        hour => [60, 60], # 1 min resolution, one hour
+        day => [60 * 30, 70], # 30 min resolution, one day
+        week => [60 * 180, 70], # 3 hour resolution, one week
+        month => [60 * 720, 70], # 12 hour resolution, 1 month
+        year => [60 * 10080, 70], # 7 day resolution, 1 year
+    };
+
     my $setup = {
-        hour => [60, 60],
-        day => [60 * 30, 70],
-        week => [60 * 180, 70],
-        month => [60 * 720, 70],
-        year => [60 * 10080, 70],
+        hour => [60, 60], # 1 min resolution
+        day => [60, 1440], # 1 min resolution, full day
+        week => [60 * 30, 336], # 30 min resolution, 7 days
+        month => [3600 * 6, 121], # 6 hour resolution, 30 days, need one more count. Otherwise RRD gets wrong $step
+        year => [3600 * 6, 1140], # 6 hour resolution, 360 days
+        decade => [86400 * 7, 570], # 1 week resolution, 10 years
     };
 
+    if ($rrdname =~ /^pve2/) {
+        $setup = $setup_pve2;
+        $timeframe = "year" if $timeframe eq "decade"; # we only store up to one year in the old format
+    }
+
     my ($reso, $count) = @{ $setup->{$timeframe} };
 
     my @args = (
-- 
2.39.5