[U-Boot] Revised NFS/TCP Tranfer measurement: Netboot Download times:: UDP vs TCP

[Simon Glass]

Hi Duncan,

On 11 June 2017 at 12:51, Duncan Hare <dh at synoia.com> wrote:
>
>
> Netboot Download times:
> u-boot NFS command (using UDP), 4 GB Linux kernel download - 16:20:45 to 16:24:07, elapsed download time 3m38 sec
>
> U-boot NFS download command.
>
> TCP Dump extract
>
> 16:20:45.666179 IP (tos 0x0, ttl 253, id 25842, offset 0, flags [DF], proto UDP (17), length 136)
>     192.168.1.129.1000 > 192.168.100.15.nfs: NFS request xid 8941 108 lookup fh Unknown/01000101000000009200400029B2975700000000000000000000000000000000 "kernel.img"
> ..
> 16:24:00.792228 IP (tos 0x0, ttl 253, id 29877, offset 0, flags [DF], proto UDP (17), length 88)
>     192.168.1.129.1000 > 192.168.100.15.46033: [udp sum ok] UDP, length 60
> 16:24:00.793398 IP (tos 0x0, ttl 64, id 60314, offset 0, flags [DF], proto UDP (17), length 52)
>     192.168.100.15.46033 > 192.168.1.129.1000: [bad udp cksum 0xe712 -> 0x2e62!] UDP, length 24
> Revised measurement on file transfer with NFS/TCP
>
> Copy same file between same machines, using NFS and TCP - 16:28:03.376601 - 16:28:043, elapsed download time approx 1sec.16:28:03.376601 IP (tos 0x0, ttl 62, id 17722, offset 0, flags [DF], proto TCP (6), length 60)    192.168.1.129.810 > 192.168.100.15.nfs: Flags [S], cksum 0x161c (correct), seq 1941867141, win 29200, options [mss 1400,sackOK,TS val 4294954943 ecr 0,nop,wscale 7], length 0..16:28:04.36833 IP (tos 0x0, ttl 62, id 46637, offset 0, flags [DF], proto TCP (6), length 52)
>     192.168.1.129.860 > 192.168.100.15.nfs: Flags [.], cksum 0xc94b (correct), seq 1673, ack 4130701, win 7356, options [nop,nop,TS val 4294956923 ecr 215895745], length 0
>
> Can the NFS command be enhanced to use TCP?
>
> TCP open source code exists in linux.kernel.org, the "net" directory. Duncan Hare
>
> 714 931 7952

I've just discovered some emails you sent to the list.

Yes I think this would be very useful, and certainly a big speed-up.

Regards,
Simon