[OpenAFS] Network becomes terribly slow when cache manager flushes updates over xDSL

Goulou fredericg_99@yahoo.fr
Tue, 7 Jul 2009 19:45:17 +0200 (CEST)


> My feeling is that #define RX_MAX_FRAG 1 instead of 4 does make
> things
> behave better if there is packet loss to be expected.

I'll try this. I noticed by searching about this field the existence of a "=
jumbo" flag : I suppose it is not in official releases yet, since /sbin/afs=
d -help doesn't mention it? (and using it gives an error...)

>=20
> About xDSL:
>=20
> It might be the case that the throttling of TCP compared to the
> throttling
> of rx (over UDP) looses when xDSL is involved. That is very difficult
> to
> predict without actually monitoring the packets on the wire in
> question.
>=20
> Another guess: It might be that your xDSL allways behaves shitty
> (like
> gets very long latency) when it gets near full. It might be that your
> provicer tunnels your xDSL over some other transport somewhere.

I had the same problem with 2 different providers (one in a large city, one=
 in in landscape), but I'll try some upload benchmarks...

Thanks again for your help.

Fr=C3=A9d=C3=A9ric Grelot.