Is shared memory no longer supported?

[ex-purple]

Hi there,
I have a problem with shared memory usage on master:
config: //CycloneDDS/Domain/SharedMemory: 'Enable': deprecated element
config: //CycloneDDS/Domain/SharedMemory: 'LogLevel': deprecated element

Is shared memory no longer supported? Or maybe this documentation is deprecated?

[eboasson]

Oops. The documentation is outdated.

The code for integrating Iceoryx used to be "hard-coded", with references to Iceoryx in various place in the Cyclone sources. We refactored it out into a plugin-based mechanism (see #1676) and added a plugin for Iceoryx in the sources. The "correct" way of configuring now looks like:

<General>
  <Interfaces>
    <PubSubMessageExchange name="iox" library="psmx_iox" config="LOG_LEVEL=INFO;"/>
  </Interfaces>
</General>

The old settings continue to work with a warning. They just translate the old (unchanging) configuration to the new format so they'll probably be around for quite some time.

[ciandonovan]

Are there plans to use this new plugin interface to provide other shared-memory providers beside Iceoryx? Maybe a daemon-less one, similar to what FastDDS does? Use the loopback just for discovery, handshakes, etc. before coordinating on the shared-memory segment to use? Have had issues with Iceoryx crashing with a large amount of nodes, would be nice if there wasn't a single point of failure as currently everything must be restarted if Iceoryx crashes AFAIK.

[eboasson]

@ciandonovan There are a few rough edges around that plug-in interface as it is stands today, but in principle, yes, the idea is that this will become a proper interface. That then gives way more freedom to use alternative ways of doing shared memory (or other pub/sub systems).