0230389593
The node blocks a certain amount of samples to use in its queues. Before this commit, the only moment to release them to the framwork was during ib_read()/ib_write(). But, there were a couple of problems. In the following I will take ib_read() as example, but ib_write() will be analogous. The first problem was: 1. If a QP disconnect, all Work Requests get invalidated and will be "flushed" to a Completion Queue. A possible solution would be, to save them in an intermediate buffer. We could then "exchange" these samples with the framework as soon as the node connects again and ib_read() is called again. So, we would get valid samples from the framwork, post them, and give the "invalidated" samples back. But, there is a second problem: 2. We cannot assume that ib_read() is ever called again after ib_disconnect(). This is for example the case if the disconnect is triggered by ib_stop() and not by an external node that disconnects. This would result in a memory leak, since the samples would never be returned to the framework, although the node is stopped. Because of this second problem, I decided to return all samples with sample_put() in the disconnect function. An additional benefit is that this is more convenient than another buffer to temporarily safe the invalidated samples. |
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| clients | ||
| cmake | ||
| doc | ||
| etc | ||
| include/villas | ||
| lib | ||
| packaging | ||
| plugins | ||
| src | ||
| tests | ||
| tools | ||
| web | ||
| .dockerignore | ||
| .editorconfig | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .gitmodules | ||
| CHANGELOG.md | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| COPYING.md | ||
| README.md | ||
VILLASnode
This is VILLASnode, a gateway for processing and forwardning simulation data between real-time simulators. VILLASnode is a client/server application to connect simulation equipment and software such as:
- OPAL-RT RT-LAB,
- RTDS GTFPGA cards,
- RTDS GTWIF cards,
- Simulink,
- LabView,
- and FPGA models
by using protcols such as:
- IEEE 802.2 Ethernet / IP / UDP,
- ZeroMQ & nanomsg,
- MQTT & AMQP
- WebSockets
- Shared Memory
- Files
- IEC 61850 Sampled Values / GOOSE
- Analog/Digital IO via Comedi drivers
- Infiniband (ibverbs)
It's designed with a focus on very low latency to achieve real-time exchange of simulation data. VILLASnode is used in distributed- and co-simulation scenarios and developed for the field of power grid simulation at the EON Energy Research Center in Aachen, Germany.
Documentation
User documentation is available here: https://villas.fein-aachen.org/doc/node.html
Copyright
2018, Institute for Automation of Complex Power Systems, EONERC
License
This project is released under the terms of the GPL version 3.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
For other licensing options please consult Prof. Antonello Monti.
Contact
- Steffen Vogel stvogel@eonerc.rwth-aachen.de
- Marija Stevic mstevic@eonerc.rwth-aachen.de
Institute for Automation of Complex Power Systems (ACS)
EON Energy Research Center (EONERC)
RWTH University Aachen, Germany