Sponsored Content
Operating Systems Linux Red Hat High RAM usage, extremely low swapping Post 302624121 by hedkandi on Sunday 15th of April 2012 11:37:01 PM
Old 04-16-2012
High RAM usage, extremely low swapping

Hi team

I have three physical servers running on Red Hat Enterprise Linux Server release 6.2 with the following memory conditions:

Code:
# cat /proc/meminfo | grep -i mem
MemTotal:        8062888 kB
MemFree:          184540 kB
Shmem:               516 kB

and the following swap conditions:

Code:
# cat /proc/meminfo | grep -i swap
SwapCached:          688 kB
SwapTotal:      10305528 kB
SwapFree:       10302584 kB

# cat /proc/sys/vm/swappiness
60

# swapon -s
Filename                                Type            Size    Used    Priority
/dev/dm-1                               partition       10305528        2944    -1

As you can see the swapspace is double the size of memory and yet the swap usage is relatively low compared to actual memory usage:

Code:
# free -mt
                     total       used       free     shared    buffers     cached
Mem:          7873       7693        179          0        380       4241
-/+ buffers/cache:       3071       4802
Swap:        10063          2      10061
Total:       17937       7696      10241

I am trying to understand why the processes are not using swap instead, but relying on RAM until it reached a critical level of 97% last weekend (sorry, haven't got the numbers all I have are charts from nagios) How can I make the process use swap instead of so much of RAM?

Having an aye-karamba moment here
Smilie
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

low RAM

Hy, I've an 486 dx2 laptop an I want to run unix on it, the problem is it has only 4 megabytes of ram, so my question is; does anybody know an unix based OS which runs with only 4 mb? thanx (7 Replies)
Discussion started by: counTnegaTive
7 Replies

2. UNIX for Advanced & Expert Users

Sun: High kernel usage & very high load averages

Hi, I am seeing very high kernel usage and very high load averages on my system (Although we are not loading much data to our database). Here is the output of top...does anyone know what i should be looking at? Thanks, Lorraine last pid: 13144; load averages: 22.32, 19.81, 16.78 ... (4 Replies)
Discussion started by: lorrainenineill
4 Replies

3. Solaris

malloc returning NULL if freemem high & swapmem low

Hi All, In my application malloc is returning NULL even though there is sufficient amount of free memory is available but swap memory is low. Is this possible that, if free memory is high & swap memory is low, malloc will not be able to allocate memory & return NULL ?:) Kindly look into... (5 Replies)
Discussion started by: Ritesh Kumar
5 Replies

4. Shell Programming and Scripting

low & high values

on the file Ftp'd from the mainframe ,do we have any UNIX command to replace mainframe low and values to space or null. i tried using tr and it doesn't work ... Thanks (1 Reply)
Discussion started by: rlmadhav
1 Replies

5. Shell Programming and Scripting

Picking high and low variables in a bash script - possible?

Is it possible to have a bash script pick the highest and lowest values of four variables? I've been googling for this but haven't come up with anything. I have a script that assigns variables ($c0, $c1, $c2, and $c3) based on the coretemps from grep/sed statements of sensors. I'd like to also... (5 Replies)
Discussion started by: graysky
5 Replies

6. Shell Programming and Scripting

Split file into chunks of low & high byte

Hi guys, i have a question about spliting a binary file into 2 chunks. First chunk with all high bytes and the second one with all low bytes. What unix tools can i use? And how can this be performed? I looked in manpages of split and dd but this does not help. Thanks (2 Replies)
Discussion started by: basta
2 Replies

7. UNIX for Advanced & Expert Users

Extremely high kernel CPU Usage (Solaris 10 SPARC)

I've got a domain running on a few boards of a 25k. I'm seeing very high kernel cpu usage in top and cant' quite explain it. System runs a large number of smallish Oracle 10g2 databases (30), used mainly for development. load average: 36.63, 36.68, 37.42 2489 processes: 2452 sleeping, 21... (0 Replies)
Discussion started by: utopiajoe
0 Replies

8. UNIX for Dummies Questions & Answers

Kernel/ user space and high/ low mem

Need some clarification on this.... 1. how are kernel/ user spaces and high/low memory related? 2. What do they all mean when i have the kernel command line as: "console=ttyS0,115200 root=/dev/sda2 rw mem=exactmap memmap=1M@0 memmap=96M@1M irqpoll" or 2. what do mem and memmap mean in... (3 Replies)
Discussion started by: dragonpoint
3 Replies

9. AIX

High Runqueue (R) LOW CPU LOW I/O Low Network Low memory usage

Hello All I have a system running AIX 61 shared uncapped partition (with 11 physical processors, 24 Virtual 72GB of Memory) . The output from NMON, vmstat show a high run queue (60+) for continous periods of time intervals, but NO paging, relatively low I/o (6000) , CPU % is 40, Low network.... (9 Replies)
Discussion started by: IL-Malti
9 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)
All times are GMT -4. The time now is 08:55 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy