niklas/cyclonedds
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

add option to prefer multicast for data

Browse source 
Sometimes it can be useful to force all data transmissions to go out via
multicasts, instead of using a unicast when a single unicast suffices.
This commit adds a General/PreferMulticast setting that, when set to
true, implements this behaviour.

It is "PreferMulticast" because readers that only advertise unicast
addresses will still receive the data via unicast.

The default behaviour is unchanged.

Signed-off-by: Erik Boasson <eb@ilities.com>
This commit is contained in:
Erik Boasson 2019-05-16 14:40:42 +02:00 • committed by eboasson
parent 2c31e4aa46
commit d723ab79ad
3 changed files with 7 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

1
src/core/ddsi/include/dds/ddsi/q_config.h
View file

@ -239,6 +239,7 @@ struct config
int tracingTimestamps;
int tracingAppendToFile;
uint32_t allowMulticast;
int prefer_multicast;
enum transport_selector transport_selector;
enum boolean_default compat_use_ipv6;
enum boolean_default compat_tcp_enable;

2
src/core/ddsi/src/q_config.c
View file

@ -244,6 +244,8 @@ static const struct cfgelem general_cfgelems[] = {
<li><i>ssm</i>: enables the use of SSM (source-specific multicast) for all non-SPDP traffic (if supported)</li>\n\
</ul>\n\
<p>When set to \"false\" all multicasting is disabled. The default, \"true\" enables full use of multicasts. Listening for multicasts can be controlled by General/MulticastRecvNetworkInterfaceAddresses.</p>") },
{ LEAF("PreferMulticast"), 1, "false", ABSOFF(prefer_multicast), 0, uf_boolean, 0, pf_boolean,
BLURB("<p>When false (default) Cyclone DDS uses unicast for data whenever there a single unicast suffices. Setting this to true makes it prefer multicasting data, falling back to unicast only when no multicast address is available.</p>") },
{ LEAF("MulticastTimeToLive"), 1, "32", ABSOFF(multicast_ttl), 0, uf_natint_255, 0, pf_int,
BLURB("<p>This element specifies the time-to-live setting for outgoing multicast packets.</p>") },
{ LEAF("DontRoute"), 1, "false", ABSOFF(dontRoute), 0, uf_boolean, 0, pf_boolean,

6
src/core/ddsi/src/q_entity.c
View file

@ -1107,7 +1107,7 @@ static void rebuild_trace_covered(int nreaders, int nlocs, const nn_locator_t *l
{
char buf[DDSI_LOCATORSTRLEN];
ddsi_locator_to_string(buf, sizeof(buf), &locs[i]);
DDS_LOG(DDS_LC_DISCOVERY, " loc %2d = %-20s %2d {", i, buf, locs_nrds[i]);
DDS_LOG(DDS_LC_DISCOVERY, " loc %2d = %-30s %2d {", i, buf, locs_nrds[i]);
for (j = 0; j < nreaders; j++)
if (covered[j * nlocs + i] >= 0)
DDS_LOG(DDS_LC_DISCOVERY, " %d", covered[j * nlocs + i]);
@ -1123,7 +1123,9 @@ static int rebuild_select(int nlocs, const nn_locator_t *locs, const int *locs_n
if (nlocs == 0)
return -1;
for (j = 0, i = 1; i < nlocs; i++) {
if (locs_nrds[i] > locs_nrds[j])
if (config.prefer_multicast && locs_nrds[i] > 0 && ddsi_is_mcaddr(&locs[i]) && !ddsi_is_mcaddr(&locs[j]))
j = i; /* obviously first step must be to try and avoid unicast if configuration says so */
else if (locs_nrds[i] > locs_nrds[j])
j = i; /* better coverage */
else if (locs_nrds[i] == locs_nrds[j])
{