RE: [ActiveDir] /3GB and/or /USERVA and/or /PAE???

[joe]

You don't want PAE, if you have sufficient RAM and a DIT that exceeds 1.5GB then you will probably want /3GB. If your DIT exceeds 2 GB, you want to start considering x64.

Here is about the best note on PAE sent to the list, you can pretty much take the words from the individual as gospel as he is one of the few people you will see an email from that is actually qualified to write ESE code and understand it.

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Brett Shirley
Sent: Monday, November 21, 2005 12:01 PM
To: ActiveDir@mail.activedir.org
Subject: RE: [ActiveDir] Microsofts Exchange Server 12 64 bit announcement

I can confirm, yes, you will only be able to deploy Exchange 12 on amd64
(well x64, i.e. including EMTWhatever) hardware.

Now, I must confess something ...

A bit over one and a half years ago (~Mar 2004, give or take a couple
months), there was this "Focus 64" campaign, posters showed up everwhere
"Focus 64 ... Shift to the power of 64-bit ... <picture of rear view
mirror, with tailgating Semi-Truck with "64" on the grill, mirror reads:>
Objects in mirror are closer than they appear."  It was just some internal
propaganda to get the development teams to be thinking and taking into
consideration 64-bit ... there are always a few of these campaign's going
on ...

Around the same time or shortly before this Exchange was still asking if
we could add PAE/AWE support to ESE like SQL.  At one point, I vaguely
remember yelling across the room, "PAE?  PAE?!?  Are you kidding me?!  We
have 64-bit desktops today!  PAE will be mueseums in five years!" (the
exact wording probably involved swear words).  I also mentioned that PAE
is a horrible hack, it makes me nauseous.  Hack up ESE because they didn't
want to port to 64-bits?  Shortly after they were waffling again!!
Wondering if they could just make it run as a 32-bit app on 64-bit OSs,
large memory aware so they could go from the ~3GB they got today to the
3.9GB of address space a large aware app gets on a amd64 based Windows OS
(that'd be a 30% increase in available memory).  They could get this if
they only ported the IFS driver to 64-bit, or removed it.  BTW, the IFS
driver is what prevents running 32-bit Exch2k3 on 64-bit OSs.  64-bit OSs
require 64-bit drivers / kernel mode components.  At which point I made a
clarifying comment to the effect of, "No, no, I want to see 48 GBs of ESE
buffer cache!  Only a native 64-bit store.exe will do.  Get off your ..."
(perhpas I felt more swear words were necessary, I don't remember)
Anyway, with all this debate on "what 64-bit support means", I just wasn't
100% convinced that Exchange was compelled enough ...

So I arranged with the guy in charge of the Focus 64 campaign to reserve
50 posters for the Exchange mailbox team's floor exclusively, and one
night I snuck over in the dead of night (or early early morning I think)
and plastered these posters up and down the mailbox team's hall, I put
64-bit posters in thier regular reserved War team room, on the back of the
dev manager's chair, and even on the back of the bathroom stall doors,
just so when they're really "concentrating", they'd be thinking 64-bit.

I mean what was I supposed to do <grin>!?, they were making JET Blue look
bad.  We've servers 1 TB worth of databases attached, and only .09 to .12%
of DB buffer cache, and email is kind of weird load, kind of 4/5ths OLTP
and 1/5th DSS, and well basically Exchange is _starved_ for memory today.
JET had multiple 64-bit binaries (the Win2k DEC Alpha binary - Sept 1999
[last shipped in Beta 3, never made it to RTM], the ia64 binaries in Sept
2001, the amd64 binaries in Mar 2003).  We had tested 64-bit Itanium DCs,
with on the order of 32 GBs of RAM, to great effectiveness for huge DIT
files.

Anyway, I'm not going to claim my persistent nagging of the mailbox team
swung the tide, I honestly think they would've come to the decision
naturally on thier own (it was the only real choice).  But did walking by
a couple hall ways of posters make them _only_ Focus 64??  I personally
don't think so, but I've confessed, so I have a clear conciousness. :) If
you need someone to blame, you can blame me personally if you like ...


Overall ...

I'm quite happy, the Exchange team stepped up to the plate, and is going
to release IMO, the killer 64-bit app.  They deserve accolades.

There are actuallly several details besides this one that make an inplace
upgrade a more difficult thing to do/support, and together these details
embolden the forced migration option.  If you read the notes from people
at the IT Forum close enough, I saw at least 2 of the other reasons that
increase the difficulty of doing in place upgrades.  We rigorously debate
these things, there are more aspects to the decision than has been
mentioned so far.

joe, I run my desktop heavily loaded, and frequently run with 200 to 300
windows open, and persistently run out of desktop heap (a kernel mode
resource, I've even increased this several times), I'm greatly
anticipating having a 64-bit desktop for "whizbang GUI stuff".

I had some comments on the cost debate, but I'll put that on another fork
of the thread ...

Cheers,
BrettSh [msft]
ESE Developer

This posting is provided "AS IS" with no warranties, and confers no
rights.



--
O'Reilly Active Directory Third Edition - http://www.joeware.net/win/ad3e.htm



________________________________

From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Mike Baudino
Sent: Monday, November 06, 2006 4:10 PM
To: ActiveDir@mail.activedir.org
Subject: Re: [ActiveDir] /3GB and/or /USERVA and/or /PAE???


Thank you Paul, Brian, and Sue,

/3GB makes sense to me as well.  We put a call into Microsoft on Saturday and were told that we wanted /PAE but not /3GB.  But all they appeared to go by were the published kb articles, which we had already gone over, not found conclusive, and hence called Microsoft.

When's the Server 2003 version of Notes from the Field going to come out??? (rhetorical...)

Any issues with /PAE and /3GB in conjunction?  We're not running enterprise but our Wintel team, who built the servers, put /PAE in the boot.ini on most of the physical boxes with 4GB phyiscal RAM.  I read, in a kb article, that /PAE and /3GB can put strain on the system.

Brian, yes, quads were serious overkill but that's what our Wintel team wanted out there.  We spec'd pizza boxes since they're in field offices.  Some FOs have upwards of 1,000 folks in them though.  35,000 across North America.

Thanks,
Mike


On 11/6/06, Paul Williams <[EMAIL PROTECTED]> wrote:

        You need 4GT enabled (/3GB switch) if these only function as DCs.  There's not much info. on this, but if you want to get the maximum LSASS footprint into RAM (~2.7GB) then you need to enable 4GT.  If you're running K3 SP1 Enterprise then PAE is enabled by default and therefore the boot.ini switch is not necessary.
        
        I don't think you need to worry about PAE although sometimes the full RAM doesn't show up unless you do enable it (or, in some cases, tweak some BIOS setting).
                
        
        --Paul

        
       
                                ----- Original Message -----
                From: Mike Baudino <mailto:[EMAIL PROTECTED]> 
                To: ActiveDir@mail.activedir.org
                                Sent: Saturday, November 04, 2006 5:30 PM
                Subject: [ActiveDir] /3GB and/or /USERVA and/or /PAE???

                
                                                Hi all,
                
                We're running a Server 2003 AD environment across 110 DCs across North America and Europe.  We have physical DCs on a variety of fairly new hardware and ESX VMs.
                
                Older server hardware, approx two years old:
                quad proc
                2GB ram
                
                ESX VMs:
                dual proc
                3.6GB ram
                
                New server hardware, from this summer:
                quad proc
                4GB ram
                
                
                Our DIT is around 2.3-2.4 GB and still growing slowly as we continue migrations of users.  Server migrations coming next.  There's no Exchange in our environment and the DCs are single-purpose as we don't permit anything else to be loaded on them (except for SYSVOL, antivirus, and monitoring tools, of course).
                
                My concern is that none of the older hardware or the VMs are running /3GB or /PAE.  Some of the new hardware is running /PAE and some is not.  I would like to have some degree of consistency.
                
                From what I can tell, running /3GB would make sense on the VMs and the newer physical boxes as it would permit more RAM to be allocated LSASS.  If we use /3GB do we need to, or want to, use /USERVA? 
                
                I don't see any advantage, and in fact a disadvantage, to running /PAE.  The disadvantage may just be "bad press" but it appears that there are issues with /PAE compatibility.  Also, it appears that /PAE has no impact at or below 4GB?
                
                I read another thread from earlier this summer that the VMs should probably be replaced.  We're looking into that but it will take a while.  The thread seemed to indicate that /3GB might be the way to go.
                
                Anyway, I would like to know what you're running and/or would recommend.  Called Microsoft about this and they looked up the same article that we already had but seemed to offer no advise based on real world experience.  You guys are where the rubber meets the road.
                
                Thanks,
                Mike