[SunHELP] 32bit/64bit

[Frank-Christian Kruegel]

On Fri, 1 Mar 2002 12:15:39 -0500, you wrote:

>How do I determine what mode the kernel is running at 32bit or 64bit.
>Is it safe to assume that the Ultra5, U10, 220R 's all have 64bit
>processors?  Haven't really covered this subject but I get asked by
>support people on Solaris based products.  My typical response is
>all our apps are 32bit.... thanks for any info.
>_______________________________________________
>SunHELP maillist  -  SunHELP at sunhelp.org
>http://www.sunhelp.org/mailman/listinfo/sunhelp

All sun4u machines have 64 bit processors, the older ones haven't. You need
to
have the 64 bit kernel running for 64 bit applications. UltraSparc 1 machines
boot the 32 bit kernel by default because the US1 processors can lock up with
a
rare 64 bit opcode sequence that doesn't occur in real life but can be used
for
DOS attacks.

isainfo shows you what applications a system can run. If it says "sparcv9
sparc"
then it runs 64 bit (sparcv9) and 32 bit (sparc) applications, ie it has a 64
bit kernel running.

You can obtain more details with the isalist command:

An UltraSparcIIi machine shows:
bash-2.03# uname -a
SunOS uaxi 5.8 Generic_108528-11 sun4u sparc SUNW,UltraSPARC-IIi-Engine
bash-2.03# isalist
sparcv9+vis sparcv9 sparcv8plus+vis sparcv8plus sparcv8 sparcv8-fsmuld
sparcv7
sparc

A SS10 with 2 Hypersparcs shows:
bash-2.02# uname -a
SunOS newsun 5.6 Generic_105181-23 sun4m sparc SUNW,SPARCstation-10
bash-2.02# isalist
sparcv8 sparcv8-fsmuld sparcv7 sparc

The items sparcv7, sparcv8 etc etc show the CPU instrction set the machine
can
execute. You might use a "higher" instruction set, which will limit you to
newer
machines. If you compile your apps for sparcv8 they won't run un sun4c
machines,
which are sparcv7 only. If you use sparcv8plus an UltraSparc cpu is required
although sparcv8plus is 32 bit code, and a 32 bit kernel is enough for
sparcv8plus.

So you can take advantage of the UltraSparc instruction set without going to
64
bit code. The openssl package on SunFreeware does (or at least did) so.

Mit freundlichen Gr|_en

Dipl.-Ing. Frank-Christian Kr|gel
IstDa Kommunikationssysteme