Re: Increasing RX buffers for xennet(4)

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Tue, Oct 29, 2024 at 09:57:39AM -0700, Brian Buhrow wrote:
> 	hello.  For some time I've seen messages of the form:
> 
> [ 68670.674458] xennet0: rx no cluster
> [ 71559.876225] xennet0: rx no cluster
> [ 72917.029633] xennet0: rx no cluster
> 
> On sevral busy domU's we use.  In looking into the issue, it appears the xennet(4) driver
> doesn't pre-allocate enough ring items for the RX buffer to keep up with the input flow from
> the network.

No, I don't think this is the issue. This message shows up when
pool_cache_get_paddr() returns a NULL va. As there's no limit on
the if_xennetrxbuf_cache pool, it means that either there's no free VA, or no
free page.

Maybe this pool_cache should be primed at some point ?


-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--