memory-monitor: disable by default.

The memory monitor is a new component with limited real-world testing.
To ensure system stability, it is now disabled by default. Users can
enable it manually if needed.

This commit updates the default value of `memory-monitor.enabled` to
`false` in the global config and documentation, reflecting the change in
behavior.

Signed-off-by: Nikolay Martyanov <[email protected]>
(cherry picked from commit 41289af)

docs/CONFIG-PROPERTIES.md

@@ -64,7 +64,7 @@
 | network.switch.enable.arpsnoop | boolean | true | enable ARP Snooping on switch Network Instances |
 | wwan.query.visible.providers | bool | false | enable to periodically (once per hour) query the set of visible cellular service providers and publish them under WirelessStatus (for every modem) |
 | network.local.legacy.mac.address | bool | false | enables legacy MAC address generation for local network instances for those EVE nodes where changing MAC addresses in applications will lead to incorrect network configuration |
-| memory-monitor.enabled | boolean | true | Enable external memory monitoring and memory pressure events handling |
+| memory-monitor.enabled | boolean | false | Enable external memory monitoring and memory pressure events handling |
 
 In addition, there can be per-agent settings.
 The Per-agent settings begin with "agent.*agentname*.*setting*"

pkg/memory-monitor/README.md

@@ -190,6 +190,10 @@ This setup allows you to toggle memory monitoring on and off, which can be
 especially useful if you suspect that the memory monitor's handler script might
 be consuming excessive CPU or memory resources.
 
+As the memory monitor is a new component in the EVE system, and very few
+real-world testing was done with it, is important to be on the safe side, so we
+disable the memory monitor by default. It can be enabled by the user if needed.
+
 ## Internals of the build and startup process
 
 To deploy the memory monitor to the EVE system, we create a corresponding

pkg/pillar/types/global.go

@@ -950,7 +950,7 @@ func NewConfigItemSpecMap() ConfigItemSpecMap {
 	configItemSpecMap.AddBoolItem(EnableARPSnoop, true)
 	configItemSpecMap.AddBoolItem(WwanQueryVisibleProviders, false)
 	configItemSpecMap.AddBoolItem(NetworkLocalLegacyMACAddress, false)
-	configItemSpecMap.AddBoolItem(MemoryMonitorEnabled, true)
+	configItemSpecMap.AddBoolItem(MemoryMonitorEnabled, false)
 
 	// Add TriState Items
 	configItemSpecMap.AddTriStateItem(NetworkFallbackAnyEth, TS_DISABLED)