Yes, shared memory is often not considered, because it can be used by many process - or it is counted several times.
A special type of shared memory is the SysV IPC (inter process communication), listed with
E.g. for the "Shared Memory" the listed PIDs are for the "Creator" and the "Last attacher".
Even the normal fork/exec to create a new process produces shared memory.
Because initially they are identical, they are not actually copied but the new process reuses the memory. They are really copied when the new process modifies it. This is called COW (copy on write).
Your last sentence is the explanation of why two identical servers have different usage of memory? To be honest i tried to read man page of ipcs. I can give you the output of those 2 servers... but i still cannot understand it....
I am about to give it up..
My next shot is to reboot the server which confuses me and check its reaction...
But i would like to have any "evidence" to approve the need of reboot!
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)
Hi Guys,
I wonder what would be the best way to determine how much memory is in use on any given time by the database processes. I thought about using ipcs -m command but I wonder if there any better way to determine this. Thanks.
Harby. (2 Replies)
Hi,
I have AIX 5.3TL8 two node cluster using HACMP and have 10g database using RAW devices. I am seeing gradual increase in comp% memory everyday and it reaches 100% and evicts the node, we had 4 evictions in 40days.
I am pasting vmstat and vmo output, anyone seen this issue?
... (5 Replies)
Hi All,
Anyone has script to monitor AIX total processes memory and cpu usage that contribute to the total memory and CPU utilize so far ?
The purpose of this is to analyze process memory trend.
Thanks.
Best Regards,
ckwan (2 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)
Discussion started by: System Admin 77
8 Replies
LEARN ABOUT DEBIAN
passenger-memory-stats
passenger-memory-stats(8) Administration Commands passenger-memory-stats(8)NAME
passenger-memory-stats - reports a snapshot of the Apache and Phusion Passenger memory statistcs
SYNOPSIS
passenger-memory-stats
DESCRIPTION
passenger-memory-stats allows you to easily analyze the real memory usage of Phusion Passenger and Apache.
Process inspection tools such as ps and top are useful, but they rarely show the correct memory usage. The real memory usage is usually
lower than what ps and top report.
There are many technical reasons why this is so, but an explanation is beyond the scope of this page. We refer the interested reader to
operating systems literature about virtual memory and copy-on-write.
When you run this tool the Private or private dirty RSS field shows the real memory usage of processes.
ENVIRONMENT VARIABLES
HTTPD The full filename to the Apache executable. By default, Passenger will attempt to autodetect the Apache executable. If autodetection
fails for whatever reason, then Apache processes will not be shown in the memory statistics. In that case, you may manually specify
the location to the Apache executable using this environment variable.
SEE ALSO passenger-status(8), ps(1), top(1),
User guide at http://www.modrails.com/documentation.html
AUTHOR
Phusion Passenger is written by Phusion (http://www.phusion.nl)
"Phusion" and "Phusion Passenger" are trademarks of Hongli Lai & Ninh Bui.
This manual page was written by Neil Wilson <neil@brightbox.co.uk> for the Ubuntu project (but may be used by others).
Phusion Passenger 2.0 passenger-memory-stats(8)