prstat and top commands don't show too much memory being used by processes and system is not using too much kernel and page cache memory, where did the system memory go?

(Doc ID 1490250.1)

Last updated on JULY 29, 2016

Applies to:

Solaris Operating System - Version 10 3/05 and later
Information in this document applies to any platform.
***Checked for relevance on 06-May-2016***

Symptoms

 

 - vmstat free column shows low values

- prstat and top commands don't show too much memory being used by processes

- mdb memstat command doesn't show high kernel or page cache usage, however it shows a greater than expected value for the "Anonymous" row.

- System might be paging out or swapping threads to swap device (vmstat's sr column greater than 0) causing performance problems.

- "ipcs -ma" or "ipcs -ZAm" shows 0 in NATTCH column and the process that created that segment (CPID) no longer exists

T         ID      KEY        MODE        OWNER    GROUP  CREATOR   CGROUP NATTCH      SEGSZ  CPID  LPID   ATIME    DTIME    CTIME  ISMATTCH         PROJECT     ZONE
m   83886104   0          --rw-rw----    40021      dbax    60022      dbax      0 34292629504 24490 24490  9:56:37  9:56:37  9:56:09        0             101 zoneX
m   83886103   0          --rw-rw----    40021      dbax    60022      dbax      0  201326592 24490 24490  9:56:09  9:56:37  9:56:09        0             101 zoneX

 

 

Cause

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