Solaris 10: Enabling 2 GB Large Pages

Few facts:

• 8 KB is the default page size on Solaris 10 and 11 as of this writing
• both hardware and software must have support for 2 GB large pages
• SPARC T4 hardware is capable of supporting 2 GB pages
• Solaris 11 kernel has in-built support for 2 GB pages
• 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: Solaris 10 8/11 (Update 10) or later
  Hardware: SPARC T4. eg., SPARC T4-1, T4-2 or T4-4
  
   
  Steps to enable 2 GB large pages on 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