jsonnet: Disable cpufreq collector in node_exporter

The node_exporter cpufreq collector seems to be causing high load on
some machines with lots of cores.  This disables it temporarily as a
workaround until the issue can be addressed upstream.  We don't seem
to rely on these metrics anywhere.

See: https://bugzilla.redhat.com/show_bug.cgi?id=1972076

assets/node-exporter/daemonset.yaml

@@ -35,6 +35,7 @@ spec:
         - --collector.netdev.device-exclude=^(veth.*)$
         - --collector.cpu.info
         - --collector.textfile.directory=/var/node_exporter/textfile
+        - --no-collector.cpufreq
         image: quay.io/prometheus/node-exporter:v1.1.2
         name: node-exporter
         resources:

jsonnet/node-exporter.libsonnet

@@ -138,8 +138,20 @@ function(params)
                       // gather that data (especially for bare metal clusters), and
                       // add flags to collect the node_cpu_info metric + metrics
                       // from the text file.
-                      args: [a for a in c.args if a != '--no-collector.hwmon'] + ['--collector.cpu.info', '--collector.textfile.directory=' + textfileDir],
-                      terminationMessagePolicy: 'FallbackToLogsOnError',
+                      args: [a for a in c.args if a != '--no-collector.hwmon'] +
+							[
+							  '--collector.cpu.info',
+							  '--collector.textfile.directory=' + textfileDir,
+
+							  // The cpufreq collector seems to be causing high
+							  // load on some nodes with lots of cores.  Disable
+							  // it temporarily as a workaround.
+							  //
+							  // https://bugzilla.redhat.com/show_bug.cgi?id=1972076
+							  // https://github.com/prometheus/node_exporter/issues/1880
+							  '--no-collector.cpufreq',
+							],
+					  terminationMessagePolicy: 'FallbackToLogsOnError',
                       volumeMounts+: [{
                         mountPath: textfileDir,
                         name: textfileVolumeName,