Bottleneck on 10Gbe

[nischu]

Hello,

thanks for this great project, it worked immediately on my machine.

However, there seems to be a performance bottleneck somewhere and I'd like to help find it. Using a 10 Gbit network, the iSCSI transfer maxes out at about 950 Mbit/s where other iSCSI kernel drivers are able to deliver around 6 Gbit/s. kernel_task uses around 40% of CPU, so there should be some room for improvement.

Can you point me to the right direction? Is there any queue size that may be the limiting factor?

Thanks a lot already
nischu

[nsinenian]

Hasn't been tested on 10 Gbit (not by myself anyway). You can try altering the performance parameters in the Info.plist file (you will need to manually unload, edit, and reload the kernel driver). You can find Info.plist inside the kext (inside the installed folder).

These are the current settings:

		<key>IOMaximumSegmentCountRead</key>
		<integer>512</integer>
		<key>IOMaximumSegmentCountWrite</key>
		<integer>512</integer>
		<key>IOMaximumSegmentByteCountRead</key>
		<integer>2048</integer>
		<key>IOMaximumSegmentByteCountWrite</key>
		<integer>2048</integer>

[systemcrash]

It's worth investigating the network adaptor, esp if you have a USB based one. Some adaptors won't lock to the higher network speeds if the bus speed is 5Gbit or lower. I encountered this recently - tho not in connection with this project.