wtmpx problem on Solaris 8 sparcv9 (64bit) environment

Darren Moffat Darren.Moffat at eng.sun.com
Sat Jun 30 01:57:46 EST 2001

>When I was using OpenSSH-2.9p2 in Solaris 8 sparcv9 (64bit)
>environment, I found some trouble that wtmpx has broken.

Why are you building 64bit binaries for ssh ?  This will gain you
nothing and there is no reason to do so.  32bit binaries run just fine
on a 64bit kernel (most of Solaris is still 32bit binaries even when
running a 64bit kernel).

There are currently only 4 reasons to compile userland binaries 64bit
rather than 32bit:

	1. The process needs greater than 4Gb address space 2. Need for
	a 64bit time_t
		ie need to process times past 2038 3. Direct access to
	kernel memory when runing a 64bit kernel 4. Need to control a
	64bit process via /proc (ie you are a debugger).

None of the ssh programs fall into these categories.

You can do 64bit maths without building a 64bit binary and you can get
UltraSPARC performance improvements on 32bit binaries - infact in
general 32bit binaries perform better than 64bit ones.

If you are compiling with -xarch=v9 in an attempt to gain the
performance benifits of the UltraSPARC platfrom then this isn't what
you are getting.  In fact all it will do is hurt your performance since
you will waste valuable cache space - bigger bits does NOT mean

-xarch=v9 means build a 64bit binary -xtarget=ultra will give you a
32bit binary optimized for UltraSPARC.

I don't believe that this patch is neccessary.

Darren J Moffat

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