User`s guide

16 Troubleshooting

16-30

“Block 23 is being dropped because packets are unavailable for resend”

and it does not mention buffer size, it is likely that packets are being dropped due

to overload of the CPU. To lower the CPU load, raise the value of the PacketSize

device-specific (source) property. In order to do this, you must be using hardware

that supports jumbo frames.

You might also want to calculate and set the PacketDelay device-specific (source)

property.

Also, if you are using a CPU that is older than an Intel Core 2 Quad or equivalent

AMD, you may experience this type of error.

If you have a slower computer and experience packet loss using the GigE Vision

adaptor, you can set a packet delay to avoid overloading the computer. This

is useful in solving the performance issue if you cannot achieve your camera’s

frame rate. The PacketDelay property will initially be set to use the value that

is your camera’s default value. You can then adjust the value if needed. The

TimeStampTickFrequency property is read-only but is available for calculating the

actual packet delay value is being used.

For more information on the new PacketDelay property and how to calculate

packet delay, see this solution:

http://www.mathworks.com/support/solutions/en/data/1-F36R0R/index.html

If you are able to start acquisition without error but do not receive any frames, and if

you are using a larger PacketSize, make sure that your hardware and the network

between the computer and the camera support jumbo frames, and also that your

Ethernet interface is set to allow them at the size that you are attempting to use.

If you receive an error that says a block or frame is being dropped because a packet

is unavailable for resend, one likely cause is that the buffer size of the socket could

not be set to the reported value, for example 1000000.

See your system administrator about using sysctl for net.core.rmem_max. For

example, the system administrator could try:

sysctl -w net.inet.udp.recvspace=1000000

If your camera does not start a new acquisition at block 1, the toolbox will attach the

block ID (frame ID) as metadata to the frame. If you want to know if you lost initial