/3GB /PAE problem

Sponsored Links

Hi,
We have a serious problem on our production cluster.
It's a MSCS cluster with 16GB RAM for each node and Windows 2003 EE
Server R2 sp2 32 bit installed on 64bit processors.
In the file boot.ini the parameter /PAE is set.
We're trying to set the /3GB flag as well but after rebooting a node ,
but we have experienced serious instability at the OS level. Windows
is not responding anymore relating
to OS basic processes that fail to start, network interfaces not
recognized anymore and other weird stuff concerning domain policies
and user environment. So we took the /3GB off the boot.ini.
Is the /3GB usable together with the /PAE parameter in such an
architecture? We thought it were, as we can see from some SAP notes
and Microsoft documents.
We also have opened a message at SAP and they confirmed this
possibility.
Moreover, starting an SAP application server and a MSSQL 2005 sp1
server on a node, we notice that from the Windows Task Manager the RAM
consumption reaches around 3
GB and afterward all the memory request goes largely into using the
paging file.
We also tried to set the windows page file to 0 (zero) (NO PAGE FILE)
but starting the database and/or the SAP application what we could see
was that in the task manager the physical memory consumption was very
low and the page file usage very high.
It seems the servers cannot address all the 16GB recognized at OS
level.
Is it possible to use all the RAM available without exploiting the OS
page file?
We are going live within few days.
Could you please tell us how to solve the problem asap?

Hardware vendor and model:
- HP DL 380 G5 with 16GB ram , HBA card for a fibre channel connection
to the storage HP EVA 4000 (HSV200-B), N° 2 local hard disk for the
local boot ( 2 x 72GB), N° 2 lan card 1000tx.
Operating system: Windows 2003 Enterprise ed. English version R2 with
SP2

Enabling PAE causes each PTE to consume twice as much memory from that
allocated to kernal mode. Using the /3GB switch takes a gig of ram away
from kernal mode and gives it to user mode. The cause of the instability is
the reduced number of free system PTEs that are now available You could:

1. Try using /USERVA=3030 or so to give a bit of memory back to kernal to
use for PTEs
2. Determine which kernal mode drivers are consuming the most, and update
those drivers
3 if all else fails, do't use the /3gb switch with /pae


"FabioG" <FabioG@discussions.microsoft.com> wrote in message
news:E7231E66-7262-42E0-AEBF-00482B1784E8@microsoft.com...
> Hi,
> We have a serious problem on our production cluster.
> It's a MSCS cluster with 16GB RAM for each node and Windows 2003 EE
> Server R2 sp2 32 bit installed on 64bit processors.
> In the file boot.ini the parameter /PAE is set.
> We're trying to set the /3GB flag as well but after rebooting a node ,
> but we have experienced serious instability at the OS level. Windows
> is not responding anymore relating
> to OS basic processes that fail to start, network interfaces not
> recognized anymore and other weird stuff concerning domain policies
> and user environment. So we took the /3GB off the boot.ini.
> Is the /3GB usable together with the /PAE parameter in such an
> architecture? We thought it were, as we can see from some SAP notes
> and Microsoft documents.
> We also have opened a message at SAP and they confirmed this
> possibility.
> Moreover, starting an SAP application server and a MSSQL 2005 sp1
> server on a node, we notice that from the Windows Task Manager the RAM
> consumption reaches around 3
> GB and afterward all the memory request goes largely into using the
> paging file.
> We also tried to set the windows page file to 0 (zero) (NO PAGE FILE)
> but starting the database and/or the SAP application what we could see
> was that in the task manager the physical memory consumption was very
> low and the page file usage very high.
> It seems the servers cannot address all the 16GB recognized at OS
> level.
> Is it possible to use all the RAM available without exploiting the OS
> page file?
> We are going live within few days.
> Could you please tell us how to solve the problem asap?
>
> Hardware vendor and model:
> - HP DL 380 G5 with 16GB ram , HBA card for a fibre channel connection
> to the storage HP EVA 4000 (HSV200-B), N° 2 local hard disk for the
> local boot ( 2 x 72GB), N° 2 lan card 1000tx.
> Operating system: Windows 2003 Enterprise ed. English version R2 with
> SP2
>
>
>

You can use both switches together, but the real question is why bother,
your already giving SQL 14 GB of the available 16 GB using the \PAE switch.
The OS needs some memory, and when you use the 3GB switch you starve the
kernal. The 3GB switch is really for systems that don't have more then 4
GB.

"FabioG" <FabioG@discussions.microsoft.com> wrote in message
news:E7231E66-7262-42E0-AEBF-00482B1784E8@microsoft.com...
> Hi,
> We have a serious problem on our production cluster.
> It's a MSCS cluster with 16GB RAM for each node and Windows 2003 EE
> Server R2 sp2 32 bit installed on 64bit processors.
> In the file boot.ini the parameter /PAE is set.
> We're trying to set the /3GB flag as well but after rebooting a node ,
> but we have experienced serious instability at the OS level. Windows
> is not responding anymore relating
> to OS basic processes that fail to start, network interfaces not
> recognized anymore and other weird stuff concerning domain policies
> and user environment. So we took the /3GB off the boot.ini.
> Is the /3GB usable together with the /PAE parameter in such an
> architecture? We thought it were, as we can see from some SAP notes
> and Microsoft documents.
> We also have opened a message at SAP and they confirmed this
> possibility.
> Moreover, starting an SAP application server and a MSSQL 2005 sp1
> server on a node, we notice that from the Windows Task Manager the RAM
> consumption reaches around 3
> GB and afterward all the memory request goes largely into using the
> paging file.
> We also tried to set the windows page file to 0 (zero) (NO PAGE FILE)
> but starting the database and/or the SAP application what we could see
> was that in the task manager the physical memory consumption was very
> low and the page file usage very high.
> It seems the servers cannot address all the 16GB recognized at OS
> level.
> Is it possible to use all the RAM available without exploiting the OS
> page file?
> We are going live within few days.
> Could you please tell us how to solve the problem asap?
>
> Hardware vendor and model:
> - HP DL 380 G5 with 16GB ram , HBA card for a fibre channel connection
> to the storage HP EVA 4000 (HSV200-B), N° 2 local hard disk for the
> local boot ( 2 x 72GB), N° 2 lan card 1000tx.
> Operating system: Windows 2003 Enterprise ed. English version R2 with
> SP2
>
>
>

Why don't you wipe your cluster nodes and start by installing the correct OS
version? The 64-bit version of Windows will not require any tweaking of RAM
/ memory parameters and you'll get superior performance with your clustered
business solution by using the proper OS for the hardware.

I know this sounds extreme, but seriously...why would you run a 32-bit OS on
this hardware configuration? I know nothing about SAP, but I'd imagine that
they have a version that is supported on a 64-bit OS. SQL is no problem at
all - it's a champ on x64!

Hope this helps (in some strange, lots-of-rework-creating way),
--Ryan

--
--
Ryan Sokolowski
MVP - Windows Server - Clustering
MCSE, CCNA, CCDA, BCFP
"FabioG" <FabioG@discussions.microsoft.com> wrote in message
news:E7231E66-7262-42E0-AEBF-00482B1784E8@microsoft.com...
> Hi,
> We have a serious problem on our production cluster.
> It's a MSCS cluster with 16GB RAM for each node and Windows 2003 EE
> Server R2 sp2 32 bit installed on 64bit processors.
> In the file boot.ini the parameter /PAE is set.
> We're trying to set the /3GB flag as well but after rebooting a node ,
> but we have experienced serious instability at the OS level. Windows
> is not responding anymore relating
> to OS basic processes that fail to start, network interfaces not
> recognized anymore and other weird stuff concerning domain policies
> and user environment. So we took the /3GB off the boot.ini.
> Is the /3GB usable together with the /PAE parameter in such an
> architecture? We thought it were, as we can see from some SAP notes
> and Microsoft documents.
> We also have opened a message at SAP and they confirmed this
> possibility.
> Moreover, starting an SAP application server and a MSSQL 2005 sp1
> server on a node, we notice that from the Windows Task Manager the RAM
> consumption reaches around 3
> GB and afterward all the memory request goes largely into using the
> paging file.
> We also tried to set the windows page file to 0 (zero) (NO PAGE FILE)
> but starting the database and/or the SAP application what we could see
> was that in the task manager the physical memory consumption was very
> low and the page file usage very high.
> It seems the servers cannot address all the 16GB recognized at OS
> level.
> Is it possible to use all the RAM available without exploiting the OS
> page file?
> We are going live within few days.
> Could you please tell us how to solve the problem asap?
>
> Hardware vendor and model:
> - HP DL 380 G5 with 16GB ram , HBA card for a fibre channel connection
> to the storage HP EVA 4000 (HSV200-B), N° 2 local hard disk for the
> local boot ( 2 x 72GB), N° 2 lan card 1000tx.
> Operating system: Windows 2003 Enterprise ed. English version R2 with
> SP2
>
>
>