Re: [RFC][PATCH 0/3] TCP/IP Critical socket communication mechanism

From: Matt Mackall
Date: Thu Dec 15 2005 - 00:54:33 EST


On Wed, Dec 14, 2005 at 09:23:09PM -0800, David S. Miller wrote:
> From: Matt Mackall <mpm@xxxxxxxxxxx>
> Date: Wed, 14 Dec 2005 21:02:50 -0800
>
> > There needs to be two rules:
> >
> > iff global memory critical flag is set
> > - allocate from the global critical receive pool on receive
> > - return packet to global pool if not destined for a socket with an
> > attached send mempool
>
> This shuts off a router and/or firewall just because iSCSI or NFS peed
> in it's pants. Not really acceptable.

That'll happen now anyway.

> > I think this will provide the desired behavior
>
> It's not desirable.
>
> What if iSCSI is protected by IPSEC, and the key management daemon has
> to process a security assosciation expiration and negotiate a new one
> in order for iSCSI to further communicate with it's peer when this
> memory shortage occurs? It needs to send packets back and forth with
> the remove key management daemon in order to do this, but since you
> cut it off with this critical receive pool, the negotiation will never
> succeed.

Ok, encapsulation completely ruins the idea.

--
Mathematics is the supreme nostalgia of our time.
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