iox-#1295 Extend FAQ with more questions

README.md

@@ -37,7 +37,7 @@ This ensures data transmissions with constant latency, regardless of the size of
 </p>
 
 You're right, middleware is a cluttered term and can somehow be all or nothing. To get a better impression what
-this means for iceoryx, please have a loot at our [goals and non-goals](doc/goals-non-goals.md).
+this means for iceoryx, please have a look at our [goals and non-goals](doc/goals-non-goals.md).
 
 Don't get too frightened of the API when strolling through the examples. Think of the untyped C++ and the C API as a
 "plumbing" one ("plumbing" as defined in Git, which means low-level). We're not using the "plumbing" APIs ourselves, but
@@ -92,7 +92,7 @@ Please see the dedicated [README.md](tools/docker/README.md) for information on
 
 ### Quality levels & platforms
 
-> [Quality level](./CONTRIBUTING.md#quality-levels) are 5 to 1+, where 1+ is highest level.
+> [Quality level](./CONTRIBUTING.md#quality-levels) are 5 to 1+, where 1+ is the highest level.
 
 Please see the [Quality Declaration](./QUALITY_DECLARATION.md) for details of the quality measures according to ROS 2 guidelines.
 

doc/website/FAQ.md

@@ -2,10 +2,59 @@
 
 In this document are tips and hints documented which can help for troubleshooting on RouDi.
 
-## Does iceoryx run in a docker environment
+## Does iceoryx run in a docker environment?
 
 Yes. Take a look at the [icedocker example](../../iceoryx_examples/icedocker/)
 
+## How can I find out if RouDi is running?
+
+RouDi uses a file locking machanism to ensure that only one RouDi instance is running at a time. For that RouDi
+creates and locks `/tmp/roudi.lock`. The file exists also also when RouDi is not running. Try locking this file,
+if this fails RouDi is running.
+
+On the command line do
+
+```console
+flock -n /tmp/roudi.lock echo "RouDi is not running"
+```
+
+## Missing samples in a publish subscribe scenario
+
+Lost samples are not acceptable for your system? Is your publisher sending at a higher frequency than the subscribers
+are taking the samples?
+
+Either
+
+* Make sure that the receiving frequency is higher than the publishing one
+
+or
+
+* Use the [blocking publisher feature](../../iceoryx_examples/iceoptions/)
+
+!!! caution
+    The usage of the blocking publisher feature needs to be considered carefully as other subscribers will not receive
+    samples while the publisher is blocked.
+
+A possible alternative is
+
+* Increase `SubscriberOptions::queueCapacity` to up to 256
+  * If 256 is not enough, increase the maximum value `IOX_MAX_CHUNKS_HELD_PER_SUBSCRIBER_SIMULTANEOUSLY`
+  via [the CMake switch](advanced/configuration-guide.md)
+
+## Solving the error `MEPOO__MEMPOOL_GETCHUNK_POOL_IS_RUNNING_OUT_OF_CHUNKS`
+
+Possible solutions are one of the following:
+
+1. Increase [memory configuration of RouDi](advanced/configuration-guide.md)
+1. Make sure that the receiving frequency is higher than the publishing one
+1. Reduce `SubscriberOptions::queueCapacity` to hold less samples in the mempool on the subscriber side
+1. Consider using the [blocking publisher feature](../../iceoryx_examples/iceoptions/). The usage needs to be
+considered carefully as other subscribers will not receive samples while the publisher is blocked.
+
+!!! caution
+    The usage of the blocking publisher feature needs to be considered carefully as other subscribers will not receive
+    samples while the publisher is blocked.
+
 ## iox-roudi fails on startup
 
 An error message like

doc/website/getting-started/overview.md

@@ -225,9 +225,16 @@ following conditions:
 to process local constructs, no dynamic allocators
 - the data structure has to be relocatable and therefore must not internally use pointers/references
 - no virtual member functions
+- must not rely on the destructor being called
 
 !!! note
-    Most of the STL types cannot be used, but we reimplemented some of them so that they meet the conditions above.
+    The sample might be released from a process without write access to the shared memory. Therefore the
+    destructor is not called when a sample is released. All data types must be either trivially destructible or must
+    at least not rely on the destructor being called. The latter is the case for the iceoryx containers like
+    `cxx::vector` where only the inner type must be trivially destructible.
+
+!!! info
+    Most of the STL types cannot be used, but some are reimplemented to meet the conditions above.
     You can find an overview [here](../../../iceoryx_hoofs/README.md#cxx).
 
 ### Publisher