Kbase 21207: What Is Priority Paging And How To Activate It?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
14/02/2011 |
|
Status: Verified
GOAL:
What Is Priority Paging And How To Activate It?
FACT(s) (Environment):
Solaris SPARC 2.6
Solaris SPARC 7
FIX:
Priority paging is a new paging algorithm which can significantly enhance system response when the file system is being used. Priority paging makes the operating system's pager give a higher priority to pages that contain code from executables and shared libraries, data in heap, and data in stacks. Higher priority means they are less eligible to be paged out except when there is a memory shortage.
This has the effect of improving overall performance by preventing the file system cache from using memory that the applications need.
Be default, priority paging is disabled. It is likely to be the basis of the default algorithm in future OS releases. Priority Paging should be activated on all Solaris systems that have it, according to Gus Bjorklund, Wizard and VP of Technology. To use priority paging requires either Solaris 2.7 or Solaris 2.6 with kernel patch 105181-09.
To enable priority paging, set the following in /etc/system:
set priority_paging=1
To enable priority paging on a live 32 bit system, set the following with adb:
# adb -kw /dev/ksyms /dev/mem
lotsfree/D
lotsfree: 730 <- value of lotsfree
cachefree/W 0t1460 <- 2 x value of lotsfree
To enable priority paging on a live 64 bit system, set the following with adb:
# adb -kw /dev/ksyms /dev/mem
lotsfree/E
lotsfree: 730 <- value of lotsfree
cachefree/Z 0t1460 <- 2 x value of lotsfree