Can anyone help me the detailed procedure and commands to follow to add additional swap on aix server .
My system shows following as of now ,
Code:
#lsattr -E -l sys0 -a realmem
realmem 13893632 Amount of usable physical memory in Kbytes False
#pstat -s
PAGE SPACE:
USED PAGES FREE PAGES
735534 837330
# lsps -a
Page Space Physical Volume Volume Group Size %Used Active Auto Type
hd6 hdisk0 rootvg 6144MB 47 yes yes lv
Please help me on finding what is the maximum swap size that i can increase? Also i need to do it without a reboot.Thanks
Moderator's Comments:
Please use CODE tags to display program input, program output, and code segments; not for your entire post.
Last edited by Don Cragun; 04-18-2016 at 10:46 PM..
Reason: Fix CODE tags.
The maximum theoretical size of one paging device is 64 GB. You have paging device hd6 which is 6 GB. Theoretically you can expand it by 56 GB.
Before expanding you have to answer the following questions:
- how much memory does your application require?
- is it possible to buy more memory, if the LPAR doesn't have enough, or to move it to another server?
- how did it happen, that you have 47% used in paging space? Which processes are now in the paging space and which of the running processes overuse the memory resources you have?
After you answered the questions and if you still want to have more paging space, you can look in rootvg using lsvg rootvg, if you have enough space in the volume group, and then create additional paging space with mkps or expand the existing with chps.
agent.kgb is absolutely correct: paging space is a "plan B", if "plan A" (memory) fails. Your system shouldn't need to use it under normal circumstance and it should be there only for contingency.
Right now you have your 13GB memory already overused to a point where ~3GB of paging space is needed. You should put in more memory (unless other data show different probably ~5GB, to cover for the 3GB already missing and some extra on top to make the system comfortably run) and only then make your paging space bigger.
The size of paging space should be in some relation to the real memory, like the size of a jerry can should reflect the cars gas consumption. And like the jerry can it should be there but under normal circumstances never be used.
It would also be interessting when the paging to PS occurs. I saw that RMAN accumulated used pgsp at nightly backup jobs (over some days/weeks) but on days peak loads had about no paging out at all.
You can monitor this by writing a small script using vmstat to have a look at the pi/po columns or have nmon installed to record it for you.
Depending on the oslevel of your OS it could also maybe handled by adjusting some tuning parameters.
If you want to investigate what is using the paging space at the moment you can issue:
Thank you for your help. I checked the physical memory being only 13GB and left the idea of increasing swap size as of now.
I will get back in case of any progress.
not every segment in AIX memory has a corresponding process.
The real command to look, what lays in paging space is something like:
Code:
svmon -S -O sortseg=pgsp -t 20
-S shows all memory segments, -O sortseg=pgsp sorts them, showing first the segments which have most pages in the paging space, -t 20 shows only first 20 segments.
This is an example from a system, which pages right now:
Code:
$ lsps -a
Page Space Physical Volume Volume Group Size %Used Active Auto Type Chksum
hd6 hdisk0 rootvg 8192MB 24 yes yes lv 0
$ svmon -S -O sortseg=pgsp -t 20
Unit: page
Vsid Esid Type Description PSize Inuse Pin Pgsp Virtual
8f61ff - work mmap paging sm 0 0 65024 65024
86078c - work sm 127 4 64405 64451
838405 - work mmap paging sm 762 0 64336 65024
820fc6 - work mmap paging sm 2521 0 62703 64770
847dc9 - work mmap paging sm 13881 0 54286 64032
825b45 - work sm 24 0 14056 14075
8c97db - work sm 224 4 10339 10475
8000 - work page table area s 6916 43 6873 6916
81de02 - work sm 3362 0 4965 6645
82dd04 - work sm 2491 0 4285 5952
8d4e5b - work sm 65 4 3694 3747
8e841d - work sm 535 0 3473 3677
8c9f59 - work sm 603 0 2611 2791
820b66 - work sm 287 0 2588 2619
8c58f9 - work sm 3443 0 2428 3497
884951 - work mmap paging sm 8192 0 2186 8192
8c1b3a - work sm 48 4 2082 2101
825965 - work m 4096 0 124 4096
1001 - work other kernel segments m 149 0 123 235
8d001a - work m 194 0 115 272
As you see, all the segments are "work" segments and some of them has "long" Vsids (virtual segment IDs), such as 8f61ff, but some of them has "short" Vsid, such as 8000. Those with long IDs are probably associated with some processes. You can look at them using the following command:
Code:
$ svmon -S 8f61ff -lrj
Vsid Esid Type Description PSize Inuse Pin Pgsp Virtual
8f61ff - work mmap paging s 0 0 65024 65024
m 0 0 0 0
Addr Range: 0..65534
pid(s)=12058694
The last string contains pid, which you can then find with ps -ef:
If you look at a segment with short Vsid, you will not see any pid:
Code:
$ svmon -S 8000 -lrj
Vsid Esid Type Description PSize Inuse Pin Pgsp Virtual
8000 - work page table area s 6916 43 6873 6916
Addr Range: 0..8703
System segment
It is a system segment and it has no corresponding process. Sometimes they can grow very big and in this case it is not an application problem, but server's configuration problem.
In the attached file I am trying to use awk to extract multiple values and create the tab-delimited desired output.
In the output R_Index is a the sequential # and Pre_Enrichment is defaulted to ..
I can extract from the values to the side of the keywords, but most are above and I can not... (2 Replies)
Hello,
How is it possible to free swap memory on AIX.
when i do vmstat on machine i can see less than 1 Gb "fre" when usually I have around 5 GB.
I dont wont to reboot the server.
any idea?
Thanks. (3 Replies)
Thanks for allwoing me to discuss in this forum
GIVEN BELOW A simple shell script which will ask for the user to input a PC name and it will produce the output in CSV with the PC name
#! /bin/bash
read -p "enter the PC name :" pc
#checking for netstat report
netstat -pant |sed '1,2d'... (1 Reply)
I need to change the following field from:
"7/3/2009 7:07:12 PM","12345676","ok","8674"
"6/3/2009 8:07:12 PM","12345676","ok","8674"
"5/1/2009 7:07:12 PM","12345676","ok","8674"
"4/9/2009 3:07:12 AM","12345676","ok","8674"
"3/8/2009 3:07:12 PM","12345676","ok","8674"
"2/7/2009 4:07:12... (10 Replies)
Hi,
I am a newbie to AIX. We have 2 AIX5.3 servers in our environment, I need to transfer some files in Binary mode from one server to another and some files in ASCII mode from one server to another server. Could you please help me as to how I need to do that?
Thanks,
Rakesh (4 Replies)
I have an unsupported legacy server:
# uname -a
AIX ibmms01 3 4 0054960A4C00
Following a period of poor performance, it was investigated using vmstat 10.
There upto 10 blocked kernel threads reported, and free memory was down to 123. The scan rate was high, 3000+ with lots of page in page... (6 Replies)
I have some problem to add a fujitsu Model MAT3147NC on my Aix 5.1 Server. When i run the cfgmrg command and after de lspv command, i can see my disk but i think it's missing some drivers to get operational.
Thank's for your help. (0 Replies)
For a project we need to make sure that all php / html files in a certain directory on the webserver are showing advertisments of us.
For example, when you get a website from Lycos, you'll have an advertisement in the right corner.
How to?
As far as I can see, Lycos includes a javascript... (1 Reply)
04-18-2016
