Performanc​e and W/R-Queue problems

Question

I'm new to NICAN programming and I'm in trouble with some weird behaviour:
To measure bus-load with "KVASER Navigator" i wrote a simple program that sends very quickly a great number of frames.
The first thing i noticed is the poor performance, reaching only about 70% of bus-load at 100K and at full processor load.
And the second, (n := number of sent frames) only
n-WRITE_QUEUE_LENGTH frames are send, the rest still is in the queue until a Queue-Overflow happens and the remaining 10 frames are sent, but at least 1 frame (which causes the Queue-Overflow still remains in the queue).
Im using Celeron-600MHz, Win2000+SP5, NICAN PCI S2 (1Port) + newest driver 2.1.2 Beta
My sourcecode: please see file-attachment CanBusLoa
dTest.cpp
Attachments:
CanBusLoadTest.cpp ‏3 KB

Answer 1

Try setting a larger write buffer. Also see this KnowledgeBase about Optimizing CAN performance:
http://digital.ni.com/public.nsf/websearch/7076642​EBC9B819986256CEE00805F60?OpenDocument