RE: RE:[sap-basis] Physical memory too low
Posted by
Admin at
|
Share this post:
|
|
0 Comments
 | Posted by Waelz, Dean on Feb 12 at 5:00 PM |  Mark as helpful |
Good Day
I believe the requirement for swap space (on Windows anyway) stems from the way that Windows crashes, and the support requirement around that process.
When Windows crashes on a production SAP server, there are probably more than a few people who want to know 'why'. In order to determine this, the "complete memory dump" may be required. The "complete memory dump" is the entire contents of the RAM, written to the disk, as a file. The Windows swap file is used in this crash/dump process. If the Windows swap file is smaller than the physical RAM size, then one cannot obtain a "complete memory dump" and therefore neither SAP nor MS support will be able to say for sure what happened.
SAP knows their own systems' characteristics & assumes that one has sized the host hardware appropriately to the installed system (i.e. that the host server will not be swapping excessively under normal operation because the RAM was planned correctly up front) therefore they can make a specific recommendation like 'RAM+14GB' - unlike MS who do not know exactly how the server is going to be used and therefore can't assume too much and so recommends less specific swap settings like 1.5*RAM or even 3.5*RAM
http://support.microsoft.com/kb/254649
Regards,
-----Original Message-----
From: D. Caddick via sap-basis [mailto:sap-basis@groups.ittoolbox.com]
Sent: February 12, 2010 12:12 PM
To: Waelz@whms9722.wshs; Dean Waelz
Subject: RE:[sap-basis] Physical memory too low
Hi Lars-Erik,
I have just checked the latest SQL Server installation Guides and this has changed again.
Details are:
1 times RAM plus 14 GB
Min Ram in a CI 6GB
Min Ram in a distributed System 4GB
Regards
---------------Original Message---------------
From: Surendra Julury
Sent: Tuesday, February 09, 2010 1:10 AM
Subject: Physical memory too low
> Hi Experts,<br/>We were monitoring the Production system today and found that the physical memory is too low.<br/>Please find the details below.<br/>load averages: 0.15, 0.23, 0.34; <br/>355 processes: 354 sleeping, 1 on cpu<br/>CPU states: 82.9% idle, 2.1% user, 1.5% kernel, 13.6% iowait, 0.0% swap<br/>Memory: 34G phys mem, 2423M free mem, 20G total swap, 17G free swap<br/>Please let us know if this is a serious problem and suggest on the same. <br/>Regards,<br/>Surendra.
__.____._ I believe the requirement for swap space (on Windows anyway) stems from the way that Windows crashes, and the support requirement around that process.
When Windows crashes on a production SAP server, there are probably more than a few people who want to know 'why'. In order to determine this, the "complete memory dump" may be required. The "complete memory dump" is the entire contents of the RAM, written to the disk, as a file. The Windows swap file is used in this crash/dump process. If the Windows swap file is smaller than the physical RAM size, then one cannot obtain a "complete memory dump" and therefore neither SAP nor MS support will be able to say for sure what happened.
SAP knows their own systems' characteristics & assumes that one has sized the host hardware appropriately to the installed system (i.e. that the host server will not be swapping excessively under normal operation because the RAM was planned correctly up front) therefore they can make a specific recommendation like 'RAM+14GB' - unlike MS who do not know exactly how the server is going to be used and therefore can't assume too much and so recommends less specific swap settings like 1.5*RAM or even 3.5*RAM
http://support.microsoft.com/kb/254649
Regards,
-----Original Message-----
From: D. Caddick via sap-basis [mailto:sap-basis@groups.ittoolbox.com]
Sent: February 12, 2010 12:12 PM
To: Waelz@whms9722.wshs; Dean Waelz
Subject: RE:[sap-basis] Physical memory too low
Hi Lars-Erik,
I have just checked the latest SQL Server installation Guides and this has changed again.
Details are:
1 times RAM plus 14 GB
Min Ram in a CI 6GB
Min Ram in a distributed System 4GB
Regards
---------------Original Message---------------
From: Surendra Julury
Sent: Tuesday, February 09, 2010 1:10 AM
Subject: Physical memory too low
> Hi Experts,<br/>We were monitoring the Production system today and found that the physical memory is too low.<br/>Please find the details below.<br/>load averages: 0.15, 0.23, 0.34; <br/>355 processes: 354 sleeping, 1 on cpu<br/>CPU states: 82.9% idle, 2.1% user, 1.5% kernel, 13.6% iowait, 0.0% swap<br/>Memory: 34G phys mem, 2423M free mem, 20G total swap, 17G free swap<br/>Please let us know if this is a serious problem and suggest on the same. <br/>Regards,<br/>Surendra.
Copyright © 2010 Toolbox.com and message author.
Toolbox.com 4343 N. Scottsdale Road Suite 280, Scottsdale, AZ 85251
Toolbox.com 4343 N. Scottsdale Road Suite 280, Scottsdale, AZ 85251
Waelz, DeanSAP Basis Helper
Posted helpful replies on 5 threads in a group to earn a Bronze Achievement
In the Spotlight
Earn Recognition for Your Contributions at Toolbox for IT. Gain Points for Community Achievements
View this thread online
Manage group e-mails
Create an FAQ on this topic
Tell us what you think
Unsubscribe from discussion
Manage group e-mails
Create an FAQ on this topic
Tell us what you think
Unsubscribe from discussion
