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Shad-o-Scan 3001/4501 Detector
Teledyne DALSA
Optimizing Settings
The performance of the 5Gigabit Ethernet connection on the host computer generally can
be improved by adjusting some settings in the NIC. The below advices refer to the
Aquantia AQtion 5Gbit NIC adaptor. For a more detailed explanation please refer to
“Network Optimization Guide (PDF)” and “Network Imaging User’s Manual (PDF)”
which is part of the Sapera LT software package.
To reduce the interrupt overhead in the host the following settings in the NIC are
advised.
Packet Size
For a good 5Gigabit Ethernet connection with minimal packet resend conditions, host
computer performance can generally be improved by increasing the data packet size.
Each streaming video packet causes an interrupt in the host computer. Therefore
increasing the packet size reduces the CPU overhead required to handle video data from
the 5GigE Vision detectors.
A standard packet can have a size up to 1500 bytes. Many network cards support a jumbo
packet mode that can extend that size up to 16Kbytes. In theory, a packet could be as
large as 16 KB, but the CRC (cycle redundancy check) containing the checksum of each
packet is not as efficient when the packet size grows larger than 9000 bytes. For this
reason
we advise to set the packet size to 9014 bytes
(jumbo packet enabled).
Some system and network card configurations may have difficulty streaming and
handling jumbo packet data. If the system is having issues than it is advisable to disable
the Jumbo Packet setting, and use standard size packets of 1500 bytes for your
application.
Interrupt Moderation
Normally, each time a packet is received by the network card, the associated driver will
receive an interrupt. Obviously, when the packet rate is very high (that is, at high transfer
rate which is common for 5GigE Vision systems), this represents significant overhead.
Most network cards have introduced an interrupt moderation mode where the card waits
