Re: [BProc] vmadump: mips port; apparenlt bug; etc

[Grant T. <gt...@sw...>]

>>>>> Erik Arjan Hendriks <er...@he...> writes:

>> Yes, I got all this working flawlessly on uniprocessor by mangling
>> all the entry and exit points to do full saves and restores.  It's
>> ugly and inefficient, but until everything actually works this will
>> have to do.

> Since you don't seem to be porting BProc, would you mind telling me
> what the application is?  Embedded something or other?

Yes, we're making a telco router sort of thing.  Formally, it's a
"PDSN", the gateway you connect through when using a cellphone for
internet access.

In reality, it speaks a PPP-over-GRE-ish protocol over T1's or ATM to
the base stations, and stock IP-over-Ethernet or various tunnelling
formats out the other end.

Internally it's approximately a 50-odd node Linux cluster with
hardware assist to divvy the packets up.  When a card gets pulled, the
simplest thing is to use vmadump to migrate a the various processes to
another card, rather than to transfer state by hand the hard way.
Since the card is going away, most of the bproc/mosix-like
"stub"-based process location transparency stuff is useful...

We're currently investigating our icache flushing implementation;
clearly the thing's got a bug since it always blows up on what should
be valid addresses ;(

--
Grant Taylor - x285 - http://pasta/~gtaylor/
Starent Networks - +1.978.851.1185