SUMMARY- Correctly installe

From: Ross Stocks (
Date: Fri Jan 31 1997 - 07:56:31 CST

                      Subject: Time: 7:40 AM
  OFFICE MEMO SUMMARY: Correctly installed memory? Date: 1/31/97

I was surprised to get only one response and one "me-too." This must be
an area that doesn't get much attention. I'm guessing that's a good thing.

Original post:

This morning I ran across the question about non-invasion looks at the
SIMMs configuration. Great. I couldn't wait to test it out on a couple of
our systems and immediately identified what looks like incorrectly
installed memory. Maybe you can verify this for me.

On a SS20 @ SunOS4.1.4 the output of devinfo -pv indicates the following

01(1) 1(16M)
04(2) 1(16M)
08(3) 1(16M)
0a(4) 1(16M)
0c(5) 1(16M)
0e(6) 1(16M)
14(7) 4(64M)
18(8) 4(64M)
1c(9) 1(16M)

Two questions:
1) Why did it not show slot 11 as the next slot following 0e? Is that
the normal numbering sequence or did our H/W folks skip a slot?

2) Totalling the above output comes to 240M. The output of dmesg
indicates 261664K. Multiplying the above by 1024K/M gives me 245760K.
What accounts for the discrepancy in the two?
OK, three questions.

Why does the dmesg mem value not come up to an even number of meg
when divided by 1024? Shouldn't it? It does on a random sampling of our
other Suns.
============================== replied with some basic pointers, reminders and
"double-checks" as well as a question that I also wonder about. That is,
Are there any rules about installing 64MB modules in relation to 16MB

My findings seem to indicate that there are not special rules. I seem to
have access to all the installed memory even though devinfo seems to
indicate that the memory was not installed "in pairs" or with like
densities grouped together.

My final question was left unanswered. Why does the mem value listed
in the output of dmesg not equal an even number of MB when divided by

I did a lot of checking on this and found that apparently this descrepancy
only occurs on 4.1.4 machines. I checked fourteen 4.1.3, three 5.4, six
5.5.1 and two 4.1.4 machines and only the 4.1.4 machines had it.

Anyone want to venture a guess on this one?

Thanks to all...


This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:11:44 CDT