Adjust timex.plugin information to be less cryptic (#12495)

Co-authored-by: Ilya Mashchenko <ilya@netdata.cloud>
Co-authored-by: Tina Luedtke <kickoke@users.noreply.github.com>

collectors/timex.plugin/README.md

@@ -6,13 +6,16 @@ custom_edit_url: https://github.com/netdata/netdata/edit/master/collectors/timex
 
 # timex.plugin
 
-This plugin monitors the system clock synchronization state on Linux nodes.
+This plugin monitors the system kernel clock synchronization state.
 
 This plugin creates two charts:
 
--   System clock synchronization state
+-   System clock synchronization state according to the system kernel
 -   Computed time offset between local system and reference clock
 
+This is obtained from the information provided by the [ntp_adjtime()](https://man7.org/linux/man-pages/man2/adjtimex.2.html) system call.
+An unsynchronized clock may indicate a hardware clock error, or an issue with UTC synchronization.
+
 ## Configuration
 
 Edit the `netdata.conf` configuration file using [`edit-config`](/docs/configure/nodes.md#use-edit-config-to-edit-configuration-files) from the [Netdata config directory](/docs/configure/nodes.md#the-netdata-config-directory), which is typically at `/etc/netdata`.

health/health.d/timex.conf

@@ -13,5 +13,5 @@ component: Clock
     every: 10s
      warn: $system.uptime.uptime > 17 * 60 AND $this == 0
     delay: down 5m
-     info: the system time is not synchronized to a reliable server
+     info: when set to 0, the system kernel believes the system clock is not properly synchronized to a reliable server
        to: silent

web/gui/dashboard_info.js

@@ -1310,9 +1310,8 @@ netdataDashboard.context = {
     },
 
     'system.clock_sync_state': {
-        info:'<p>The system clock synchronization state. '+
-        'It is strongly recommended having the clock in sync with reliable NTP servers. Otherwise, '+
-        'it leads to unpredictable problems. '+
+        info:'<p>The system clock synchronization state as provided by the <a href="https://man7.org/linux/man-pages/man2/adjtimex.2.html" target="_blank">ntp_adjtime()</a> system call. '+
+        'An unsynchronized clock may be the result of synchronization issues by the NTP daemon or a hardware clock fault. '+
         'It can take several minutes (usually up to 17) before NTP daemon selects a server to synchronize with. '+
         '<p><b>State map</b>: 0 - not synchronized, 1 - synchronized.</p>'
     },