02-27-2010
Hi Nibbsbitt,
you are running currently between 70 and 80% computational memory on an oracle box. Since oracle is doing its processing in memory and each DB connection is forking 1 to n processes which each require their own amount of memory, IBM and oracle recommend to keep the computational memory around 70-75% and never to exceed 80% on an AIX box. Performance problems with Oracle usually start somewhere between 80 and 90% since for each forked process first memory needs to get freed up - depending on the amount of DB connections this can be a big workload.
I would be interested in your free list in peak times (output of vmstat -I 5 5) to be more clear but right now I would say that you are not yet in trouble but you should either consider adding memory in the near future because you will be when the DB continues growing or other options to reduce memory consumption (review SGA sizes - they tend to be way too big). In addition make sure that lru_file_repage is set to 0.
Hope that helps
kind regards
zxmaus
10 More Discussions You Might Find Interesting
1. AIX
good morning
what is the better solution to examen a P570 ?
because i use topas and nmon, and the results are totally different !!!
with nmon, i have 80% free cpu, and with nmon, i have 90% of used cpu !!!!!!
i take a shot with an intervall of 10s during 10 mn.
thank you (0 Replies)
Discussion started by: pascalbout
0 Replies
2. AIX
Anyone ever experienced a core dump when running NMON. I am running AIX 5.3 on an 8 CPU LPAR (P570). This has only recently started to happen. (3 Replies)
Discussion started by: johnf
3 Replies
3. AIX
Can any one help where i can find articals about nomn
I need to know how to read this tools
┌─CPU-Utilisation-Small-View───────────────────────────────────────────────────┐
│ 0----------25-----------50----------75----------100│
│CPU User% Sys% Wait% Idle%| ... (3 Replies)
Discussion started by: habuzahra
3 Replies
4. AIX
HI Im new on this world.
Im working with nmon and I understand that this tool generates a files that later with excel I can see the graphcial of my server.
The problem is that this process is execute manualy and I need to meake automatic.
How can I do That.
Sorry for my english!! :o (3 Replies)
Discussion started by: jegtoro
3 Replies
5. AIX
Hi,
I want to know how to use nmon in aix?
I have donwloaded nmon (2 Replies)
Discussion started by: manoj.solaris
2 Replies
6. AIX
We have processes that run on our AIX box that sometimes run away and end up consuming 99% of the CPU. I'd like to create a script that would attempt to monitor when this happens and send an email alert with the PID and CPU %. Has anyone done such a thing? I know that you can run the nmon output to... (6 Replies)
Discussion started by: ssmith001
6 Replies
7. Red Hat
Hi guys,
as per subject i am setting up NMON for the above OS but it is 64-bit Linux.
I downloaded the 32-bit NMON for RHEL45 as it is the only one available for RHEL45.
However, I ran into problem with the binary file.
# ./nmon_x86_rhel45
./nmon_x86_rhel45: error while loading shared... (13 Replies)
Discussion started by: DrivesMeCrazy
13 Replies
8. AIX
Hi All,
First of all, I am a DBA and not an AIX admin. I am new at using this NMON tool.
In interactive mode, I can start nmon, push 't' to have the list of process with their statistic (ie cpu% etc.).
I would like to know if there is a way to redirect that screen output into a log... (1 Reply)
Discussion started by: Nayas
1 Replies
9. Shell Programming and Scripting
Hi, my name is Steve Ngai from Malaysia. This is my first post. Hope to learn more about Unix from this forum.
My first question is can nmon be customized? When I run nmon, I need to manually type c to see CPU usage, then m for memory usage. Can I pass it some nmon option to automatically see... (2 Replies)
Discussion started by: ngaisteve1
2 Replies
10. Infrastructure Monitoring
Dear All,
I am an performance tester. Now i am working in project where we are using linux 2.6.32. Now I got an oppurtunity to learn the monitoring the server. As part of this task i need to do analysis of the Nmon report. I was completely blank in this.
So please suggest me how to start... (0 Replies)
Discussion started by: iamsengu
0 Replies
FREE(1) User Commands FREE(1)
NAME
free - Display amount of free and used memory in the system
SYNOPSIS
free [options]
DESCRIPTION
free displays the total amount of free and used physical and swap memory in the system, as well as the buffers and caches used by the ker-
nel. The information is gathered by parsing /proc/meminfo. The displayed columns are:
total Total installed memory (MemTotal and SwapTotal in /proc/meminfo)
used Used memory (calculated as total - free - buffers - cache)
free Unused memory (MemFree and SwapFree in /proc/meminfo)
shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo)
buffers
Memory used by kernel buffers (Buffers in /proc/meminfo)
cache Memory used by the page cache and slabs (Cached and SReclaimable in /proc/meminfo)
buff/cache
Sum of buffers and cache
available
Estimation of how much memory is available for starting new applications, without swapping. Unlike the data provided by the cache or
free fields, this field takes into account page cache and also that not all reclaimable memory slabs will be reclaimed due to items
being in use (MemAvailable in /proc/meminfo, available on kernels 3.14, emulated on kernels 2.6.27+, otherwise the same as free)
OPTIONS
-b, --bytes
Display the amount of memory in bytes.
-k, --kibi
Display the amount of memory in kibibytes. This is the default.
-m, --mebi
Display the amount of memory in mebibytes.
-g, --gibi
Display the amount of memory in gibibytes.
--tebi Display the amount of memory in tebibytes.
--pebi Display the amount of memory in pebibytes.
--kilo Display the amount of memory in kilobytes. Implies --si.
--mega Display the amount of memory in megabytes. Implies --si.
--giga Display the amount of memory in gigabytes. Implies --si.
--tera Display the amount of memory in terabytes. Implies --si.
--peta Display the amount of memory in petabytes. Implies --si.
-h, --human
Show all output fields automatically scaled to shortest three digit unit and display the units of print out. Following units are
used.
B = bytes
K = kibibyte
M = mebibyte
G = gibibyte
T = tebibyte
P = pebibyte
If unit is missing, and you have exbibyte of RAM or swap, the number is in tebibytes and columns might not be aligned with header.
-w, --wide
Switch to the wide mode. The wide mode produces lines longer than 80 characters. In this mode buffers and cache are reported in two
separate columns.
-c, --count count
Display the result count times. Requires the -s option.
-l, --lohi
Show detailed low and high memory statistics.
-s, --seconds delay
Continuously display the result delay seconds apart. You may actually specify any floating point number for delay using either .
or , for decimal point. usleep(3) is used for microsecond resolution delay times.
--si Use kilo, mega, giga etc (power of 1000) instead of kibi, mebi, gibi (power of 1024).
-t, --total
Display a line showing the column totals.
--help Print help.
-V, --version
Display version information.
FILES
/proc/meminfo
memory information
BUGS
The value for the shared column is not available from kernels before 2.6.32 and is displayed as zero.
Please send bug reports to
<procps@freelists.org>
SEE ALSO
ps(1), slabtop(1), top(1), vmstat(8).
procps-ng 2016-06-03 FREE(1)