?
Solved

Memory State of Health

Posted on 2001-07-05
5
Medium Priority
?
819 Views
Last Modified: 2013-12-27
Sun Solaris E250 running SunOS 5.6
512 MB Physical Memory
Approx. 1.5 GB Swap Space

I need to determine the "state of health" of memory on this server. I have run many monitors which includes multiple variations on the vmstat and sar commands. Unfortunately, I'm not a UNIX admin, and I am trying to determine what the results mean. I have included the results below.

Here are my questions:
It looks to me like swapping is not a problem on this server. Paging does occur, but isn't some paging normal? What is a normal range? Am I out of the normal range, and must I increase physical memory on this server? Are 188.06 address translation faults per second excessive, and what can reduce that number?

Swapping:
vmstat 5 10 and sar -w 5 10 indicate 0 swapping

Paging:
vmstat 5 10 indicates
==> 0-12kb pi
==> 1-60kb po

vmstat -S 5 10 indicates
==>1-38kb pi,
==>4-22kb po

sar -g 5 10 indicates an avg of
==> 2.84 pgout/s,
==> 2.86 ppgout/s,
==> 4.14 pgscan/s

sar -p 5 10 indicates an avg of
==> 1.64 pgin/s
==> 1.68 ppgin/s
==> 188.06 vflt/s

sar -r 5 10 indicates an avg of
==> 1057 freemem
==> 3,236,369 freeswap

Thanks.
0
Comment
Question by:wren2000
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
5 Comments
 
LVL 14

Expert Comment

by:chris_calabrese
ID: 6257057
First off, do you have performance issues?  If not, this is all sort of a non issue.

Next, more memory will almost _always_ make a Solaris machine faster.  That's because Solaris will use any available memory as a disk cache.

As for swapping vs. paging, the default Solaris behavior is to only swap when there is a severe memory shortage.  So zero swapping indicates that you don't have one.

Finally, to see if your programs are actually getting squeezed for memory, you want to run vmstat -p so you can see a breakdown of the different paging data.  In particular, you want to see that apo and epo are low, as the others could be high on a busy system, even when there's no memory shortage.

If apo and epo are much higher when the system is having performance issues, then you need more memory.

Curiously, however, the sol-7 boxes I have document the -p switch but don't implement it...
0
 

Author Comment

by:wren2000
ID: 6257092
I appreciate your response...

1) This server is an Oracle database backend for a web site. I wanted to determine the state of memory on the box because I have consultants telling me they will be adding 61 application connections to the system compared to the 14 they have now. I really need to know whether or not the system in its current state can handle that many additional processes, and I wanted to start with how well it is handling the current load.

2) I tried to run vmstat -p, but that switch isn't recognized on my system. Only -cisS are recognized.

Thanks!
0
 
LVL 14

Accepted Solution

by:
chris_calabrese earned 1200 total points
ID: 6257105
Unless you have another machine in a test lab that you can load the new applications on and test their memory usage, there's really not much you can do here.  Not to mention that other things beside memory can be bottlenecks (cpu, disk throughput, etc.).
0
 
LVL 21

Expert Comment

by:tfewster
ID: 8051519
No comment has been added lately, so it's time to clean up this Topic Area.
I will leave a recommendation for this question in the Cleanup topic area as follows:

- Answered by chris_calabrese

Please leave any comments here within the next 7 days

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER !

tfewster
Cleanup Volunteer
0
 

Expert Comment

by:SpideyMod
ID: 8100126
per recommendation

SpideyMod
Community Support Moderator @Experts Exchange
0

Featured Post

Want to be a Web Developer? Get Certified Today!

Enroll in the Certified Web Development Professional course package to learn HTML, Javascript, and PHP. Build a solid foundation to work toward your dream job!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In tuning file systems on the Solaris Operating System, changing some parameters of a file system usually destroys the data on it. For instance, changing the cache segment block size in the volume of a T3 requires that you delete the existing volu…
I have been running these systems for a few years now and I am just very happy with them.   I just wanted to share the manual that I have created for upgrades and other things.  Oooh yes! FreeBSD makes me happy (as a server), no maintenance and I al…
This video shows how to set up a shell script to accept a positional parameter when called, pass that to a SQL script, accept the output from the statement back and then manipulate it in the Shell.
In a previous video, we went over how to export a DynamoDB table into Amazon S3.  In this video, we show how to load the export from S3 into a DynamoDB table.
Suggested Courses
Course of the Month11 days, left to enroll

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question