Dennis writes:
> Is there support for large mbufs in v4.0? (that is, allocations of any size?)
>
There are 2 ways to use large mbufs:
o options MCLSHIFT=XXXX in your kernel config file.
Where XXX is 1 << XXX bytes. Eg, MCLSHIFT=12 is 4K mbuf clusters,
MCLSHIFT=13 is 8k clusters, etc. config will complain, but it will
work.
There are several drawbacks to this method. The most glaring is that
you'll probably be wasting an awfully large amount of space.
o allocate & manage them yourself, using m_ext mbufs, within the
subsystem you feel needs them. See the Tigon (sys/pci/if_ti.c)
driver's management of jumbo frame receive buffers for an example
of how this is done.
Hope this helps,
Drew
------------------------------------------------------------------------------
Andrew Gallatin, Sr Systems Programmer http://www.cs.duke.edu/~gallatin
Duke University Email: [EMAIL PROTECTED]
Department of Computer Science Phone: (919) 660-6590
To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-hackers" in the body of the message
