Am working on small program that used to calculate the memory usage of AIX servers. Am using svmon -G command to get the memory usage. For example, consider the following output.
Am using "in use" value at the 6-th line number as memory usage. It gives 26 % as a memory usage. Also am using /bin/ps -eo comm,pmem,args to get the all the process memory usage to confirm with previous calculation.But value calculated by both methods does not match.
Please advise.
Moderator's Comments:
edit by bakunin: my first advice is to use CODE-tags. Its the button misleadingly labeled "CODE" (in case you can't find it).
Hi All,
I have a question, can you guys please help me by giving your valuable suggestons:
I am using AIX 5L, running oracle 7 version. I need to increase the oracle memory to 40 MB more. Currently Oracle occupies 260M. I wanted to know whether I can increase the memory without any problem.... (1 Reply)
Hi All,
I have a question, can you guys please help me by giving your valuable suggestons:
I am using AIX 5L, running oracle 7 version. I need to increase the oracle memory to 40 MB more. Currently Oracle occupies 260M. I wanted to know whether I can increase the memory without any problem.... (3 Replies)
Hi,
We have AIX 5.1 machine of RAM 8 GB and paging space is 8GB. we are getting high memory usage of almost 99%.Can anybody please help in this ?
Partial vmstat o/p
kthr memory
----- -----------
r b avm fre
2 1 278727 1143
There is no paging issue.Becoz in... (5 Replies)
How to find the memory utilization of AIX server using svmon -G output.
Sample output for svmon -G command from my AIX test server,
size inuse free pin virtual
memory 4014080 3995443 18637 575916 1876393
pg space 1179648 ... (3 Replies)
Hi All,
I have some questions regarding the performance, MEMORY/ Virtual Memory (paging /swap space)
Please see the nmon-MEMORY stats from my AIX LPAR.
24 GB --> RAM
3456 MB --> Paging Space
│ Memory ───────────────────────────────────────────────────────────────────────
│... (8 Replies)
Hi, i have 2 identical web servers using AIX. I use nmon analyser to check their performance.
The server A exceeds 20% memory usage for system, 5% for cache and the rest 75% for processes. While, it uses 4% of Paging Space.
The server B exceeds 20% for system, 45% for cache and 35% for processes.... (24 Replies)
Discussion started by: dim
24 Replies
LEARN ABOUT X11R4
posix_madvise
POSIX_MADVISE(3) Linux Programmer's Manual POSIX_MADVISE(3)NAME
posix_madvise - give advice about patterns of memory usage
SYNOPSIS
#include <sys/mman.h>
int posix_madvise(void *addr, size_t len, int advice);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
posix_madvise():
_POSIX_C_SOURCE >= 200112L
DESCRIPTION
The posix_madvise() function allows an application to advise the system about its expected patterns of usage of memory in the address range
starting at addr and continuing for len bytes. The system is free to use this advice in order to improve the performance of memory
accesses (or to ignore the advice altogether), but calling posix_madvise() shall not affect the semantics of access to memory in the speci-
fied range.
The advice argument is one of the following:
POSIX_MADV_NORMAL
The application has no special advice regarding its memory usage patterns for the specified address range. This is the default
behavior.
POSIX_MADV_SEQUENTIAL
The application expects to access the specified address range sequentially, running from lower addresses to higher addresses.
Hence, pages in this region can be aggressively read ahead, and may be freed soon after they are accessed.
POSIX_MADV_RANDOM
The application expects to access the specified address range randomly. Thus, read ahead may be less useful than normally.
POSIX_MADV_WILLNEED
The application expects to access the specified address range in the near future. Thus, read ahead may be beneficial.
POSIX_MADV_DONTNEED
The application expects that it will not access the specified address range in the near future.
RETURN VALUE
On success, posix_madvise() returns 0. On failure, it returns a positive error number.
ERRORS
EINVAL addr is not a multiple of the system page size or len is negative.
EINVAL advice is invalid.
ENOMEM Addresses in the specified range are partially or completely outside the caller's address space.
VERSIONS
Support for posix_madvise() first appeared in glibc version 2.2.
CONFORMING TO
POSIX.1-2001.
NOTES
POSIX.1 permits an implementation to generate an error if len is 0. On Linux, specifying len as 0 is permitted (as a successful no-op).
In glibc, this function is implemented using madvise(2). However, since glibc 2.6, POSIX_MADV_DONTNEED is treated as a no-op, because the
corresponding madvise(2) value, MADV_DONTNEED, has destructive semantics.
SEE ALSO madvise(2), posix_fadvise(2)COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
Linux 2017-09-15 POSIX_MADVISE(3)