|
|
Sponsored Content
Operating Systems
AIX
SWAP SIZE Recommended.
Post 302564465 by zxmaus on Thursday 13th of October 2011 05:46:59 PM
10-13-2011
Moderator
While I totally agree with literally every word Bakunin said... if you start paging you do not need bigger paging spaces you need more memory 
A healthy AIX box with sufficient physical does not page (at least not after AIX 5.3 when lru_file_repage has been switched off as it should be).
I would like to add a few things.
If you start swapping, one of your major problems will not be the size of your paging space but how fast you can access it. So more smaller swapspaces of same size on different 'idle' disks make much more sense than one big slow swap area.
Apart from this, AIX cannot manage swapspaces bigger 34 GB. So if you want to go really with big paging areas, than create at least 2 of them - same size but smaller 34 GB.
Regarding SAP - actually their recommendation (and similar as well for oracle and sybase) on current AIX boxes with sufficient memory is
up to 4 GB memory - 2x size of memory + 256 MB
4 - 16 GB memory - size of memory
17+ GB - 1/2 size of memory + 4 GB
Regards
zxmaus
A healthy AIX box with sufficient physical does not page (at least not after AIX 5.3 when lru_file_repage has been switched off as it should be). I would like to add a few things.
If you start swapping, one of your major problems will not be the size of your paging space but how fast you can access it. So more smaller swapspaces of same size on different 'idle' disks make much more sense than one big slow swap area.
Apart from this, AIX cannot manage swapspaces bigger 34 GB. So if you want to go really with big paging areas, than create at least 2 of them - same size but smaller 34 GB.
Regarding SAP - actually their recommendation (and similar as well for oracle and sybase) on current AIX boxes with sufficient memory is
up to 4 GB memory - 2x size of memory + 256 MB
4 - 16 GB memory - size of memory
17+ GB - 1/2 size of memory + 4 GB
Regards
zxmaus
|
|
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hy all,
i've a little problem with the size of the swap. I've an old solaris machine, with 4Go, and swap is taking 500Mo for only 1% used at any time.
So : how can i change this size without problems ?????
(ok it may be a stupid question, but it's a real problem when you lose about 1 or 2... (3 Replies)
Discussion started by: Olivier
3 Replies
2. UNIX for Dummies Questions & Answers
Hello all,
I just got a laptop with redhat linux 7.2 installed, but during the installation the installer only put 1gig of sawp space( this laptop has 1gig of RAM). To my understanding when creating swap space, the size is determine by double the RAM. Therefore my question is that how do I... (2 Replies)
Discussion started by: larry
2 Replies
3. HP-UX
We increased our server's RAM 8 -> 32 GB RAM. swap memory is currently 10 GB. With which command I can increase this memory? (1 Reply)
Discussion started by: akyuceisik
1 Replies
4. Solaris
I have a machine: SunOS <server> 5.9 Generic_117171-15 sun4u sparc SUNW,Sun-Fire-480R
It has these filesystems:
Filesystem size used avail capacity Mounted on
/dev/md/dsk/d0 19G 15G 3.9G 80% /
/proc 0K 0K 0K 0% /proc... (6 Replies)
Discussion started by: son_t
6 Replies
5. Programming
how can I write a function to swap to different sized string? (2 Replies)
Discussion started by: rupeshkp728
2 Replies
6. UNIX for Dummies Questions & Answers
few questions
a. where can I find the RAM of a server? im about to install redhat on a server (reformat). need to know because it will be my basis for swap size. i saw something line 3048MB detected upon boot. is this the memory?
b. what is the command in lunux to check the original size of... (2 Replies)
Discussion started by: lhareigh890
2 Replies
7. Solaris
Dear All,
How to increase the swap size when physicall memory reaches 60 %. OR it can be only done after the physicall memory is full.
Rgds
Rj (8 Replies)
Discussion started by: jegaraman
8 Replies
8. Solaris
Hi All,
I want to know how to understand the actual swap size.
My o/p shows as below
root@ecovs1a # swap -s
total: 4546056k bytes allocated + 358856k reserved = 4904912k used, 5046688k available
root@ecovs1a # swap -l
swapfile dev swaplo blocks free
/dev/md/dsk/d31 ... (9 Replies)
Discussion started by: vivek.goel.piet
9 Replies
9. HP-UX
Hi Experts,
Need your advise in determining the size of swap space in of the new HP-Ux server.
Server is having 32G of physical memory.
Ideally what amout of physical memory should be allocated as a swap space?
Following document from HP suggests to have minimum swap space... (2 Replies)
Discussion started by: sai_2507
2 Replies
10. Solaris
Hi,
the /tmp size is less whereas the size allocated to swap is quite big. how to increase the size of /tmp -
#: swap -l
swapfile dev swaplo blocks free
/dev/md/dsk/d20 85,20 8 273096 273096
#: swap -s
total: 46875128k bytes allocated + 2347188k reserved =... (2 Replies)
Discussion started by: psb74
2 Replies
LEARN ABOUT HPUX
unlockable_mem
unlockable_mem(5) OBSOLETE unlockable_mem(5) NAME
unlockable_mem - OBSOLETE kernel tunable parameter DESCRIPTION
The tunable is obsolete and has been removed. Memory locking allows the privileged user to specify which pages need to remain in memory, and unaffected by the swap process. This fea- ture allows you to ensure that memory access times are unaffected by delays introduced by memory paging and swapping. For example, locking is a tool provided to privileged users on a system that is short on physical memory. Instead of having these privileged processes swap like the rest of the processes, they can lock portions of their address space. Once the pages are locked in for the privileged processes, they will no longer have to worry about memory contention. The unprivileged processes however, will have to compete for memory. provides you with a limiting factor on this privileged behavior, by setting the amount of memory which cannot be locked by user processes. WARNINGS
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation, some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun- able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was factory installed on your system, see at AUTHOR
was developed by HP. Tunable Kernel Parameters unlockable_mem(5)