Slow connection performance with ssh2

[Hans Werner Strube]

Gregory Leblanc <gleblanc at linuxweasel.com> wrote:
> > As my hardware is slower (Sparc LX, NetBSD, 50 MHz CPU) it takes more 
> > than 2 minutes (!!), which are spent on CPU cycles in ssh and sshd - running
> > with 95% CPU... - the overall CPU time used by sshd for a successful
> > connect is about 2:50 minutes
> 
> Older SPARCs in general are bloody slow at encryption operations.  Try
> upgrading to 2.9.9p2, and make sure that you're -not- using DSA, as
> that's REALLY REALLY slow.

It is important to use a matching instruction set. My openssl libcrypto
was compiled for sparcv8 (with Sun Workshop 5.0, -xO3). When using ssh
(client) on old sun4c (sparcv7) machines like IPX or SS2, ssh login took
almost 2 minutes. When a libcrypto was built specially for sparcv7,
this was reduced to 17 seconds -- of course, still much too slow.
A Sparc LX has about the same speed as an IPX but is sparcv8a (almost v8);
but if your libcrypto happens to be compiled for UltraSPARC (v8plus), you
may have a similar effect as I had.
AFAIK, gcc uses sparcv8 by default.