Questions tagged [free]
For questions about free, the command-line tool that displays the amount of free and use memory in a system. This tag shouldn’t be used for questions where free happens to be used; it’s appropriate for questions about free’s behaviour, options, sources of information, or the meaning of the information displayed by free.
38 questions
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Obtain memory values in SAR the same way as in FREE
I'd like to know if I can get memory in sar the same way I get it from free.
Currently free shows me a memory usage of 47.06% (16956/36027)*100 [used/total x 100]. Whereas sar is showing me a usage of ...
- 111
-3
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2
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94
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Error parsing memory value in bash script: expected integer expression
I have the following script to check free memory,
#!/bin/bash
THRESHOLD="500"
FREE_MEM=$(free -mh | awk '/^Mem:/{print $4}')
if [ "$FREE_MEM" -lt "$THRESHOLD" ]; then
...
0
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2
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345
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Why is Linux not using RAM but only Swap?
How can such an output of free -m be explained?
total used free shared buff/cache available
Mem: 32036 1012 225 3 8400 ...
- 181
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1
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629
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Free RAM memory from free command and Mobaxterm
I have several servers running Debian 10 or 11.
I use Mobaxterm (Link) for SSH into the servers to check the status of the services and the RAM usage.
I notice that the
free --mega -t
shows a amount ...
- 129
0
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1
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61
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Logging sum of Mem and Swap from free command output
In relation to this:
https://unix.stackexchange.com/a/754252/582781
Solution 1:
free -g -s2 | sed -u -n 's/^Mem:\s\+[0-9]\+\s\+\([0-9]\+\)\s.\+/\1/p' >> memory.log
Is there a way to add Swap to ...
0
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1
answer
110
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Low memory vs total memory in "free" command
I am trying to understand the output of the free command on an AWS Linux server. For example, free -h gives:
total used free shared buff/cache available
Mem: ...
- 103
0
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2
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593
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Getting only used memory from free command every few seconds
It was explained e.g. here:
Get separate used memory info from free -m command
how to cut the output of free command. But I want to do this every few seconds and log it to a file. So I tried:
free -g -...
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0
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179
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DELL R730XD 256GB memory but just showed 251GB on linux with command `free -h` and `htop` , why?
A DELL R730XD server with 32GiB * 8, totaling 256GB of memory, is correctly recognized as 256GB in the BIOS. When checking the memory information using "dmidecode -t memory" in Linux, the ...
- 21
0
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0
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5k
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linux drop_cache using "echo 3 > /proc/sys/vm/drop_caches" not working as expected
In our production environment we are running drop cache command echo 3 > /proc/sys/vm/drop_caches to free the RAM. But also what I found is dropping caches is not a good practice and also it won't ...
- 103
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400
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Why the numbers of "free" don't add up?
This is a side question when I try to figure out why my Ubuntu18.04 server keeps using up memory and mysql gets killed from time to time.
total used free shared buff/cache ...
- 143
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1
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4k
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what is the different between Buffer Cache that displayed from free command VS the available memory [closed]
we have 463 RHEL 7.6 machines in the cluster most of then are HDFS machines ( datanode )
from free -g command we can that usually buff/cache is around 30-50 when total memory is 256G
as I know - a ...
- 14k
2
votes
2
answers
3k
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Zero free swap but 56GiB free memory?
I have a CentOS7.9 system showing 56GiB free RAM (free -m) but only 1MiB free swap, and it's been in this state for three days. The original problem report was that a large (EE simulation) app keeps ...
- 21
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1
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1k
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need RAM & SWAP Memory monitoring Threshold
I wish to setup monitoring alerts upon used memory percentage.
I had setup 0-80% used RAM as Green (good)
81-90% as yellow(acceptable)
91-95% as orange(warning)
96+ as Red(critical)
However, i see ...
- 527
0
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2
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99
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When to upgrade RAM based on free output [closed]
I have a java application that runs on a Linux server with physical memory(RAM) allocated as 12GB where I would see the normal utilization over a period of time as below.
sys> free -h
...
- 143
0
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0
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257
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htop command displays 996GB instead of 1024GB for RAM
I have a little issue that I can't understand.
I have 8x128GB sticks of RAM, which makes 1024GB of RAM.
But the command htop displays 996G and not 1024G as expected.
You can see the following ...
