- Community Home
- >
- Servers and Operating Systems
- >
- Operating Systems
- >
- Operating System - HP-UX
- >
- Re: SHMMAX too high?
Categories
Company
Local Language
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Discussions
Discussions
Forums
Forums
Discussions
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Community
Resources
Forums
Blogs
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-11-2005 01:12 AM
тАО02-11-2005 01:12 AM
SHMMAX too high?
We have an HP-UX 11.11 system running Oracle 10g. This system was setup before I came here and they are running into some performance problems - which I believe are related to the code. Anyway, while I was digging around the system I found the SHMMAX value to be alot higher than what I though it should be. Basically we have 8GB of memory and 4GB of swap. I always thought that your SHMMAX could not be higher than the total of both memory and swap, but ideally should be set at what your amount of available memory is....which I always put and didn't include the swap. Therefore, the max it should be is around 12GB, but this system is set to 17GB. Is that alright, or could this cause problems if it is too high? I have seen documents stating what will happen if it is too low, but nothing on how high it can go.
Thanks,
Sally
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-11-2005 01:23 AM
тАО02-11-2005 01:23 AM
Re: SHMMAX too high?
No - it's more of a threat than a problem.
Having it higher than could possibly be used just means that it's possible for *one* process to use it all up.
And yes - the max that should be set is = to total RAM. But again that's unobtainable because the kernel itself will be using RAM.
Just speak with the DBAs & find out how many SIDs they'll be running & what each one's SGA declares for RAM usage & set the value to approx 10-20% higher than that total. That should suffice.
HTH,
Jeff
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-11-2005 01:36 AM
тАО02-11-2005 01:36 AM
Re: SHMMAX too high?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-11-2005 01:43 AM
тАО02-11-2005 01:43 AM
Re: SHMMAX too high?
Thanks!
S.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-11-2005 01:43 AM
тАО02-11-2005 01:43 AM
Re: SHMMAX too high?
The reason you have to follow the Oracle guidelines, even though that amount of memory can not actually be allocated is the Oracle setup program checks the kerneal parameters and won't install unless you play nice.
After installation, if you lower it and call Oracle support with an issue, they'll ask you to run a data collection script and tell you to put shmmax right back up before they work the call.
This robotic response is hard on sysadmins, and shows Oracle did not understand the HP-UX OS when they built the install check scripts.
The 25% rule protects you from actual damage and peformance problems as a result of Oracles mistake.
SEP
Owner of ISN Corporation
http://isnamerica.com
http://hpuxconsulting.com
Sponsor: http://hpux.ws
Twitter: http://twitter.com/hpuxlinux
Founder http://newdatacloud.com
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-13-2005 08:23 AM
тАО02-13-2005 08:23 AM
Re: SHMMAX too high?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
тАО02-13-2005 04:06 PM
тАО02-13-2005 04:06 PM
Re: SHMMAX too high?
the Pre-Install checks (metalink note: 283731.1)should have identified this problem amongst others (if any).
The following tests are carried out:
* OS certified?
* Other O_Hs in PATH?
* oraInventory perms
* /tmp adequate?
* Swap (in Mb)
* RAM (in Mb)
* SwapToRAM OK?
* Disk Space OK?
* Kernel params OK?
* Links and libs OK?
* Got ld,nm,ar,make?
* ulimits OK?
* User in /etc/passwd?
* Got OS packages?
* Got OS patches?
* Other OUI up?
* Group in /etc/group?
* Input ORACLE_HOME
* ORACLE_HOME valid?
* O_H perms OK?
* Umask set to 022?
* LDLIBRARYPATH unset?
* SHLIB_PATH unset?
hope this helps!
regards
yogeeraj