RE: Linux and huge pages

From: Bobak, Mark <>
Date: Wed, 23 Jan 2013 08:47:50 -0500
Message-ID: <>

Very cool. I wasn't aware of the 'AUTO' option. I'll need to play around with that one!

Unfortunately, if you're looking to directly confirm whether a particular memory segment was allocated with hugepages, I know of no way to do that.

I think it's probably possible, but I can't think of how.

You can look at /proc/meminfo, and see how many hugepages are allocated system wide, and how many of them are in use.

You can look at alert.log to see if hugepages were used (and how many) when the instance was started.

You can look at 'sysresv' (in $ORACLE_HOME/bin) to see which memory segments are associated with a specific instance.

Hope that helps,


-----Original Message-----

From: [] On Behalf Of CRISLER, JON A Sent: Tuesday, January 22, 2013 6:59 PM
To: oracle-l
Subject: Linux and huge pages

We are trying to come up with a script to troubleshoot hugepages setup in Linux. I see there is a parameter for USE_LARGE_PAGES which in has 4 different values:

True - use huge pages if available, otherwise use regular mem False- don't use huge pages
Only- only use huge pages, and if huge pages are not sufficient, throw an error and shutdown instance. Auto- new in - use oradism to reconfigure kernel to allocate huge pages

(this is a subset of Oracle Support technote 1392497.1).

My question- is there a view or a method to determine where oracle is actually using the huge pages ? Something besides sysctl or cat /proc/meminfo, ideally similar to v$sgainfo.

-- Received on Wed Jan 23 2013 - 14:47:50 CET

Original text of this message