Performance

use perftest_app  test 4194304 Throughput in 1Gbp,but Mbps only 300+，how to test large datalen's Throughput reach  900Mbpps?

pub

./perftest_cpp -pub -dataLen 4194304

sub

./perftest_cpp -sub -dataLen 4194304

How to use Persistance service for keeping data and publishing without delay

Hello, I am trying to create 20 topics on the same domain. I create a DataWriter and a DataReader for each topic. But when I create everything, I find that 15 out of 20 of the DataReaders do not receieve any messages from the DataWriters on the topic, even though the DataReaders have matched DataWriters on the domain.

Does anyone know what might be going on?

We are using unbound sequences and hence need to set the QoS property:
memory_manager.fast_pool.pool_buffer_max_size

Then the question came up, what happens if the fast_pool is dropped entirely, and memory management is handed over to an external memory manager?

Has anybody done any performance measurements comparing fast_pool memory allocation with for instance tcmalloc?

We are trying to reduce the number of QoS profiles that we need to maintain, and still get reasonable performance. We run a mix of frequent small samples, and less frequent very big samples.

Hi,

When profiling our DDS application it seems like a write call will lead to that serialization is performed even in the case when no-one is subscribing to the topic. Is that observation correct? And if so, is there any way around this so that we can reduce the overhead related to write calls on unsubscribed topics.

Our use case is for logging of pretty big data types which by default is disabled but for troubleshooting purposes we want to be able to turn it on at runtime.

BR,

Christian

Hello,

I have written code that periodically takes specific number of samples (complex data) each time. I am traversing the received samples to collect dynamic data (read only) building a json object that will be sent to a db.
I am facing a series issue with network blocking/delay.

My assumption is that several concurrent threads (take thread and other conversion threads) are accessing the rti infrastructure resulting some sort of network blocking.

Further info:
I've got several threads:

1) Thread responsible for the take operation.

Hi there

If I run a publisher and subscriber pair, I get an average of 150k samples per second. Once I enable the persistence service (writing to disk) in addition to the regular subscriber, the sample rate falls to about 2k samples per second.

I surely must have a configuration problem?!

I'm using the default configuration file in rti_connext_dds-6.0.0/resource/xml/RTI_PERSISTENCE_SERVICE.xml

Any pointers are greatly appreciated!

Thanks,

Ben

Hi,

I set up the RTI DB Integration Service to store samples of DDS and I used MySQL for the RDBMS.
I wanted to know how many samples are stored in a second, so I tested.

And the result was embarrassed, because under 100 samples were stored in a second.
(Of course, I published more than 100 samples per a second from a localhost datawriter.)

Trying to understand the causes of this error, how it's reported, and how to narrow down possible solutions

Hi

I have two questions;

1- What is the data overhead of DDS Connext v 5.2.0? I read a document about it (https://www.rti.com/hubfs/docs/DDS_Over_Low_Bandwidth.pdf) which said it is 56 byte. But I'm wondering where the dynamic data and dynamic type of every packet are stored. I think they definitely need more space.

2- Is it possible to increase domain ID size? It's 8 bits (0 to 232 plus reserved IDs) (For example increase it to a 16 bits word)

Thanks in advance for your answer :)