Dear Konstantin,
Thank you very much for your reply and detailed information.
I would appreciate if you could help us.
> I can also suggest that on your frontend SOC/FPGA machine, you boot linux
> using the "nfs-root" method. This way, the local flash memory only
> contains a boot loader (and maybe the linux kernel image, depending on
> bootloader limitations). The rest of the linux rootfs can be on your
> central development machine. This way management of flash cards,
> confusion with different contents of local flash and need to make backups
> of frontend machines is much reduced.
As you said, we can run complete Linux (Ubuntu 16) on ZYNQ and I'm using common NFS
system now. However, I didn't know "nfs-root" method which you mentioned and this method
seems to be reasonable way to just share linux rootfs.
First of all, I will try this method for simpler system.
> If you use a fast SSD and ZFS with deduplication, you will also have good
> performance gain (NFS over 1gige network to server with fast SSD works
> so much better compared to the very slow SD/MMC/NAND flash).
>
> I can point you to some of my documentation how we do this.
I'm concerned about such performance and I have checked the performance with common NFS
over gige network and my DAQ PC roughly(data transfer rate ~ O(10) MByte/sec). However, I
didn't know the ZFS and also how we can have performance gain with a fast SSD and ZFS.
Please let me know your documentation how to do it if possible.
> I would say you are on a good track. For early development on just one board,
> pretty much any way you do it will work, but once you start scaling up
> beyound 3-4-5 frontends, you will start seeing benefits from common NFS-mounted
> home directories, NFS-root booted linux, etc.
I'm developing with just one board and common NFS-mounted now. I'm looking forward to
seeing such benefits when I will use multiple frontends.
> And of course you may want to study the existing ND280/FGD DAQ. I hope you
> have access to the running system at Jparc. If not, I have a copy of
> pretty much everything (except for running hardware, it is stored in the basement,
> dead) and I can give you access.
I don't have access to the system at Jparc, but Nick has told us where FGD DAQ code is.
Is bellow URL everything of code of FGD DAQ?
https://git.t2k.org/hastings/fgddaq/-/tree/master
Best regards,
Soichiro |