ntp: shorten minimum allowed polling interval

With the filter option it is useful to collect NTP measurements at
a higher rate.

diff --git a/doc/chrony.conf.adoc b/doc/chrony.conf.adoc
index fc22b6b0b33714927d77e89d946239d9715c204a..864990db9afbbefa3e1e996608ac195a1a15e948 100644 (file)
--- a/doc/chrony.conf.adoc
+++ b/doc/chrony.conf.adoc
@@ -69,7 +69,7 @@ options:
 This option specifies the minimum interval between requests sent to the server
 as a power of 2 in seconds. For example, *minpoll 5* would mean that the
 polling interval should not drop below 32 seconds. The default is 6 (64
-seconds), the minimum is -4 (1/16th of a second), and the maximum is 24 (6
+seconds), the minimum is -6 (1/64th of a second), and the maximum is 24 (6
 months). Note that intervals shorter than 6 (64 seconds) should generally not
 be used with public servers on the Internet, because it might be considered
 abuse. A sub-second interval will be enabled only when the server is reachable
@@ -79,7 +79,7 @@ should be in a local network.
 This option specifies the maximum interval between requests sent to the server
 as a power of 2 in seconds. For example, *maxpoll 9* indicates that the polling
 interval should stay at or below 9 (512 seconds). The default is 10 (1024
-seconds), the minimum is -4 (1/16th of a second), and the maximum is 24 (6
+seconds), the minimum is -6 (1/64th of a second), and the maximum is 24 (6
 months).
 *iburst*:::
 With this option, the interval between the first four requests sent to the

diff --git a/ntp_core.c b/ntp_core.c
index 09d59af25f83875515ec3d9ceac956baa02844aa..5e40e9001001a7a1d1a2da81da246777b3e4291c 100644 (file)
--- a/ntp_core.c
+++ b/ntp_core.c
@@ -221,7 +221,7 @@ static ARR_Instance broadcasts;
 
 /* Spacing required between samples for any two servers/peers (to
    minimise risk of network collisions) (in seconds) */
-#define MIN_SAMPLING_SEPARATION 0.02
+#define MIN_SAMPLING_SEPARATION 0.002
 #define MAX_SAMPLING_SEPARATION 0.2
 
 /* Randomness added to spacing between samples for one server/peer */
@@ -268,7 +268,7 @@ static ARR_Instance broadcasts;
 #define MAX_MAXDELAYDEVRATIO 1.0e6
 
 /* Minimum and maximum allowed poll interval */
-#define MIN_POLL -4
+#define MIN_POLL -6
 #define MAX_POLL 24
 
 /* Enable sub-second polling intervals only when the peer delay is not