Preventative measures:
If you have not yet done so, limit ZFS ARC cache to RAM/4 in /etc/system:
Code:
set zfs:zfs_arc_max = 8192000000
Also watch /tmp; have a cleanup routine, and limit it to RAM/3 in /etc/vfstab:
Code:
swap - /tmp tmpfs - yes size=10240m
--
Separate measurement of RAM and swap can be done for statistics - but rarely for alert thresholds.
Instead you should measure the virtual memory, as given by "vmstat" or "swap -s". It is roughly the sum of RAM and swap.
I need to put a program together to determine the total, available memory and total and available swap on unix machines. I have been searching for weeks and I seem to run into dead ends. Every unix platform I look at has a different way to determine memory info.
Any sugggestions or new... (4 Replies)
All,
The (fre) coloumn of the (vmstat) command, does it report the size of the free list including the swap space or it only report on the RAM (physical memory).
BR, (1 Reply)
Hi friends
i have a query.
we have two p-series machine(p550 & p570) with HACMP 5.3 and AIX 5.3 hosting SAP.
Now i need to now is there a way or a command to check the memory utilization on these machines on daily basis. I have tried vmstat and iostat but still it's not clear.
We have... (3 Replies)
Hello All,
I am trying to create a script that will give me the processes that consume swap in %.
i am using the below line to get it done.
virtual=`echo "$virtual/$swp*100"|bc -l|sed -e "s/\(\.\).*/\1/g"`
but getting the following output after running it.
.039
.110
I want the... (3 Replies)
Hi Experts,
Our servers running Solaris 10 with SAP Application. The memory utilization always >90%, but the process on SAP is too less even nothing.
Why memory utilization on solaris always looks high?
I have statement about memory on solaris, is this true:
Memory in solaris is used for... (4 Replies)
Hi,
I am new to AIX, Can someone please help me how to know the swap space, total physical memory and system cache?
We are using AIX 5.3.
Thanks! (3 Replies)
Hi,
i am new to linux/RHEL 6.0 and i have two questions.
1) How to get the CPU utilization and Memory Utilization of all Services running currently?
2) How to get the CPU utilization and Memory Utilization of all Applications running currently?
Please help me to find the script.
... (2 Replies)
Discussion started by: nossam
2 Replies
LEARN ABOUT CENTOS
free
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)
free Unused memory (MemFree and SwapFree in /proc/meminfo)
shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo, available on kernels 2.6.32, displayed as zero if not available)
buffers
Memory used by kernel buffers (Buffers in /proc/meminfo)
cached Memory used by the page cache (calculated as Cached - Shmem in /proc/meminfo - the Cached value is actually the sum of page cache
and tmpfs memory)
OPTIONS -b, --bytes
Display the amount of memory in bytes.
-k, --kilo
Display the amount of memory in kilobytes. This is the default.
-m, --mega
Display the amount of memory in megabytes.
-g, --giga
Display the amount of memory in gigabytes.
--tera Display the amount of memory in terabytes.
-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 = kilos
M = megas
G = gigas
T = teras
If unit is missing, and you have petabyte of RAM or swap, the number is in terabytes and columns might not be aligned with header.
-c, --count count
Display the result count times. Requires the -s option.
-l, --lohi
Show detailed low and high memory statistics.
-o, --old
Display the output in old format, the only difference being this option will disable the display of the "buffer adjusted" line.
-s, --seconds seconds
Continuously display the result delay seconds apart. You may actually specify any floating point number for delay, usleep(3) is
used for microsecond resolution delay times.
--si Use power of 1000 not 1024.
-t, --total
Display a line showing the column totals.
--help Print help.
-V, --version
Display version information.
FILES
/proc/meminfo
memory information
SEE ALSO ps(1), slabtop(1), top(1), vmstat(8).
AUTHORS
Written by Brian Edmonds.
REPORTING BUGS
Please send bug reports to <procps@freelists.org>
procps-ng September 2011 FREE(1)