Few facts:

• 8 KB is the default page size on Oracle Solaris 10 and 11 as of this writing
• Both hardware and software must have support for 2 GB large pages
• SPARC T4 processors are capable of supporting 2 GB pages
• Oracle Solaris 11 kernel has in-built support for 2 GB pages
• Oracle Solaris 10 has no default support for 2 GB pages
• Memory intensive 64-bit applications may benefit the most from using 2 GB pages

Prerequisites:

• OS: Oracle Solaris 10 8/11 (Update 10) or later
• Hardware: Oracle servers with SPARC T4 processors e.g., SPARC T4-1, T4-2 or T4-4, SPARC SuperCluster T4-4

Steps to enable 2 GB large pages on Oracle Solaris 10:

1. Install the latest kernel patch or ensure that 147440-04 or later was installed

   • Check the patch download instructions
2. Add the following line to /etc/system and reboot

   • set max_uheap_lpsize=0x80000000

3. Finally check the output of the following command when the system is back online

   • pagesize -a

   eg.,

   % pagesize -a
   8192		<-- 8K
   65536		<-- 64K
   4194304		<-- 4M
   268435456	<-- 256M
   2147483648	<-- 2G
   
   % uname -a
   SunOS jar-jar 5.10 Generic_147440-21 sun4v sparc sun4v
   

Also See:

• Solaris 9 or later: More performance with Large Pages (MPSS)
• Large page support for instructions (text) in Solaris 10 1/06
• Solaris: How To Disable Out Of The Box (OOB) Large Page Support?
• Memory fragmentation / Large Pages on Solaris x86