Slow rate of Aravis Fake Camera module

[kuzhylol]

I`m working on Raspberry Pi setup which runs arv-fake-gv-camera-0.8 instance and sends Test Pattern:

arv-fake-gv-camera-0.8 -i eth1

But I faced the issue that the receiving part has the rate which is not more that 12 MiB/s. But I hope to see at least 100MiB/S. If I reduce the MTU (on both interfaces) and packet size on sending part, the rate will slower (as expected). Also, if tune the FPS parameter, the rate is changed. So, I use the possible maximum - 1000 HZ.

On the Aravis Fake module part I've tuned the packet size (MTU) in the next way: arv_fake_camera_write_register (fake_camera, ARV_GVBS_STREAM_CHANNEL_0_PACKET_SIZE_OFFSET, 9000);

I've checked the traffic (GVSP packets) via wireshark and I am sure that RPi sends an honest size of the MTU.

$ ./src/arv-camera-test-0.8
Looking for the first available camera
vendor name            = Aravis
model name             = Fake
device serial number   = GV01
image width            = 640
image height           = 480
horizontal binning     = 1
vertical binning       = 1
exposure               = 10000 µs
gain                   = 0 dB
payload                = 307200 bytes
gv n_stream channels   = 1
gv current channel     = 0
gv packet delay        = 0 ns
gv packet size         = 9000 bytes
 29 frames/s -    8.91 MiB/s
 34 frames/s -    10.4 MiB/s
 33 frames/s -    10.1 MiB/s
 34 frames/s -    10.4 MiB/s
 33 frames/s -    10.1 MiB/s
 33 frames/s -    10.1 MiB/s
 34 frames/s -    10.4 MiB/s
 33 frames/s -    10.1 MiB/s
 33 frames/s -    10.1 MiB/s
 34 frames/s -    10.4 MiB/s
 34 frames/s -    10.4 MiB/s
 34 frames/s -    10.4 MiB/s
 34 frames/s -    10.4 MiB/s
 35 frames/s -    10.8 MiB/s
^C 34 frames/s -    10.4 MiB/s
n_completed_buffers    = 501
n_failures             = 0
n_underruns            = 0
n_timeouts             = 0
n_aborteds             = 0
n_missing_frames       = 0
n_size_mismatch_errors = 0
n_received_packets     = 18537
n_missing_packets      = 0
n_error_packets        = 0
n_ignored_packets      = 0
n_resend_requests      = 0
n_resent_packets       = 0
n_resend_ratio_reached = 0
n_resend_disabled      = 0
n_duplicated_packets   = 0
n_transferred_bytes    = 154075536
n_ignored_bytes        = 0

Camera description:

• Model: Aravis Fake Camera
• Interface: GigE Vision (Ethernet)

Platform description:

• Aravis version: 0.8.6
• OS: GigE Vision Source - RPi, GigE Vision sink - Ubuntu 20 LTS
• Hardware: Raspberry Pi 4B, Standard x86 PC with Gigabit Ethernet NIC
• Cable: Cat 6e
• Connection: Point to point (directly)

[EmmanuelP]

Hi,

Did you check the CPU use on the raspberry ? No effort has been made to make the fake camera efficient yet, as it is mainly a testing tool for the aravis library.

[kuzhylol]

Yes, I have checked that CPU load is less than 80%. Maybe you can get some advice how I could improve the performance?

[EmmanuelP]

You can dive into src/arvfakecamera.c and arvgvfakecamera.c. The code is quite simple, I'm not sure what is to be optimized.

You may try to create a static test pattern. That would use less CPU.

[EmmanuelP]

I have just checked again. The performance is mainly limited by the CPU, and also the network interface on a raspberry pi 2 (about 4MB/s). So a static pattern would definitely improve things.