diff options
| author | guest <guest@da047780-0f9f-48de-953f-cd541ee48bbd> | 2007-10-11 17:04:39 +0000 |
|---|---|---|
| committer | guest <guest@da047780-0f9f-48de-953f-cd541ee48bbd> | 2007-10-11 17:04:39 +0000 |
| commit | 3e088cfbbf5fefa728e8c333838eaadbaf93a64c (patch) | |
| tree | ec18cdd54d9261a27e768c4b40b2d784f3a0c06f | |
| parent | 9f6398676910a35847f114b8c3f3ca53af134d0b (diff) | |
1 sentence conclusion
git-svn-id: svn+ssh://mecka.net/home/svn/rtcorba-paper@10 da047780-0f9f-48de-953f-cd541ee48bbd
| -rwxr-xr-x | paper.tex | 4 |
1 files changed, 2 insertions, 2 deletions
@@ -185,11 +185,11 @@ An TAO ORB can only schedule its CORBA requests correctly, if the underlying ope The operating system should support priorization of device i/o data. The real-time application must not beeing interrupted by incomming traffic on any device, excepted data the real-time application must react on (e.g. digital inputs). On a RT\_PREEMPT enabled linux, the most part of all ISR\footnote{interrupt service routine}s are done in kernel threads, which can be priorized from userspace. This solution has two little cons: IRQ sharing and the softirqs for networking. IRQ sharing prevents from a real per device priorization. The softirqs for networking handle the traffic of all NICs in the system. So the priorization of network data from a specific device is not possible. But in case real-time networking gets more and more important, the community works on a solution for this issue.
-real-time capable network drivers
-
+Not all NICs (especially their firmware and driver) are good for real-time networking. Many modern NICs don't request an interrupt for each received package. They only request an interrupt if a defined amount of data is received, or a defined timeout is over. Esspecially for real-time network communications with little data transfer, these cards causes high latencies.
\section{Conclusion}
+Using an object-orientated middleware for real-time communication over standard ethernet hardware, is especially in the automation industrie, not a trivial thing. But with ACE/TAO and RT\_PREEMPT enabled Linux it is no longer science-fiction.
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