[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [microblaze-uclinux] Network performance

Hi,

Thanks! 15 mbps sounds great. :-)
I have been working more with the system, and learned more. Now I am able to run uClinux with the mch_opb_ddr core. My initial problem was actually that I had to adjust the phase shift of the dcm_1 module (from 19 to 16 now) with the new ddr controller. I though this phase shift was only dependant on the actual delay on the pcb, but the delay must be changing inside the fpga also then.
sgDMA is also enabled on the emac. uClinux finds it, and it works very stable now with the mch_opb_ddr. My only problem is that even with all these enhancements the rate only increased to 4 to 5 mbps. It is indeed much more responsive and faster.
Which programs should I use to benchmark the network? So far I have used netcat, ftp and nfs. tcp and udp seem to give same bandwidth. This probably means that I'm not limited by the cpu but rather bandwidth on the bus? 


Thanks for great help and support on a great OS!



--
Sincerely Mattis



On Wed, 5 Apr 2006, John Williams wrote:


Hi Mattis,

With the mch_opb_ddr core, and the ethernet mac in scatter-gather DMA
mode, 15 MBPs is easily achievable.  There is a new version of the emac
core on the way, which improves things even further.

See my specific comments below:


It is currently running at 66MHz. I have more or less followed a ml401
howto from the uclinux microblaze homepage. I have enabled scatter
gather dma, but this makes uclinux crash whenever I try to download
anything. I get an ip through the dhcp client though. Is it any trick I
need to know to get this working?


I'm not aware of any issues in the ethernet driver, with or without
SGDMA enabled. Can you provide more details?


I have enabled the barrel shifter also. Caches are enabled and 16kb,
does it exist an howto on how to make the multichannel memory controller
with "XCL-bus caching" to work? Is it possible to run uclinux with this,
and will it help on the network performance?


Yes - I've found these memory controllers give an immediate 2x
performance improvement in real terms.


Is 10mbit a realistic goal with uClinux on ML401, or do I have to run a
single tcp/ip stack; or change to a power pc cpu (inside a more
expensive fpga)?


It's realisitc on MicroBlaze - no need for a PPC for that.

Regards,

John
___________________________
microblaze-uclinux mailing list
microblaze-uclinux@xxxxxxxxxxxxxx
Project Home Page : http://www.itee.uq.edu.au/~jwilliams/mblaze-uclinux
Mailing List Archive : http://www.itee.uq.edu.au/~listarch/microblaze-uclinux/




--
mvh Mattis
___________________________
microblaze-uclinux mailing list
microblaze-uclinux@xxxxxxxxxxxxxx
Project Home Page : http://www.itee.uq.edu.au/~jwilliams/mblaze-uclinux
Mailing List Archive : http://www.itee.uq.edu.au/~listarch/microblaze-uclinux/