Free memory

From: Joe Smith <>
Date: Fri, 19 Mar 2010 09:14:35 -0500
Message-ID: <BLU108-W15C3280AC7CB5F5DE11683972A0_at_phx.gbl>

How does Oracle/SunSolaris handle the “Free SGA Memory available”?  

My sga_target=384M


I use the ipcs –a command to see the size my of Shared Memory segment for the db:  

SEGSZ=734011392   If I select from v$sgainfo:  

Free SGA Memory Available 331350016    

My question is:  

My shared memory segment is 700M,
my sga_max_size is 700M,
my sga_target is 384M
my Free SGA is 316M  

How does Oracle/Sun at the OS level handle that free memory in the shared memory segment? Is it reserved only for Oracle processes or can other users claim some of that memory if the system is under pressure? Does the OS “lock” or set aside that memory region and say “I know you are not using this now, but I am going to restrict access to it from other users and hold it for only you (i.e. Oracle processes ).  


Hotmail is redefining busy with tools for the New Busy. Get more from your inbox.
Received on Fri Mar 19 2010 - 09:14:35 CDT

Original text of this message