pty(4) 1024 bytes buffer limit

[Matthew Mondor <mm_lists%pulsar-zone.net@localhost>]

Hello,

I've been wondering if it was possible to change the pty(4) internal
buffer size, as I noticed that ppp tunnels cannot use a larger frame
size.  Because of this, it seems that the optimal MTU be 856, which is
so small that context switches become the bottleneck.

It would be nice to for instance be able to use an MTU of 3000 so that
there are less context switches, but unfortunately tracing the
processes show that 1024 bytes are read from the pty devices at most.

I looked at the various tty(4) termios(4) and pty(4) without finding an
option to change the buffer size.  Is there a way at all to change it?

Thanks,
-- 
Matt