Fujitsu M10-1/M10-4/M10-4S: Memory consumption by ldom manager and hypervisor

Asset ID:	1-71-1611376.1
Update Date:	2017-03-27
Keywords:

Solution Type Technical Instruction Sure

Solution 1611376.1 : Fujitsu M10-1/M10-4/M10-4S: Memory consumption by ldom manager and hypervisor

Applies to:

Fujitsu M10-1 - Version All Versions to All Versions [Release All Releases]
Fujitsu M10-4S - Version All Versions to All Versions [Release All Releases]
Fujitsu M10-4 - Version All Versions to All Versions [Release All Releases]
Oracle Solaris on SPARC (64-bit)

Goal

Explain the memory consumption by ldom manager and the hypervisor in the Fujitsu M10 systems.

Solution

We noticed that when, in this case, 256 GB Memory is installed that prtdiag shows only 260053 Mb as available. (256 GB RAM is actually 262148 MB) This is roughly 2 Gb less then installed.

What consumes the missing two GB RAM ?

Cause

If you add 1792MB ( 1GB + 384 MB + 128 MB + 248 MB ) to the size reported by prtdiag 260352 ---> 262148MB = 256GB

root@M10-4s-ppar0:~# ldm ls-devices -a mem
MEMORY
PA SIZE BOUND
0x780000800000 1G _sys_      *
0x780040800000 384M _sys_    *
0x780058800000 128M _sys_    *
0x780060800000 248M         *
0x780070000000 63744M primary
0x7a0000000000 64G primary
0x7c0000000000 64G primary
0x7e0000000000 64G primary

root@M10-4s-ppar0:~# prtdiag | head
System Configuration: Oracle Corporation sun4v SPARC M10-4S
Memory size: 260352 Megabytes

So what we see is that the ldom manager together with the hypervisor layer
that consumes the memory.

Attachments

This solution has no attachment