Skip to main content
Share Your Experience: Take the 2024 Developer Survey

Questions tagged [meminfo]

This is one of the more commonly used files in the /proc/ directory, as it reports a large amount of valuable information about the systems RAM usage.

Filter by
Sorted by
Tagged with
0 votes
0 answers
23 views

What's left unaccounted by /proc/meminfo

What is the proper formula to understand distribution of MemTotal - MemFree? On a system where Huge pages are almost not utilized I assume that it should be the sum of the following stats: page cache ...
Maksym L's user avatar
2 votes
1 answer
1k views

Linux server high memory usage without applications

I have an Ubuntu 20.04.4 server with 32GB RAM. The server is running a bunch of LXD containers and two VMs (libvirt+qemu+kvm). After startup, with all services running, the RAM utilization is about ~...
user2653646's user avatar
1 vote
1 answer
4k views

Why is VmallocTotal 34359738367 kB?

/proc/meminfo has a memory statistic VmallocTotal. It is described as Total size of vmalloc memory area. in proc's man page and elsewhere as Total memory available in kernel for vmalloc allocations ...
Arthur Tarasov's user avatar
4 votes
2 answers
1k views

How to diagnose high `Shmem`? (was: Why `echo 3 > drop_caches` cannot zero the cache?)

I have a problem with my Linux machine where system now seems to run easily out of RAM (and trigger OOM Killer) when it normally can handle similar load just fine. Inspecting free -tm shows that buff/...
Mikko Rantalainen's user avatar
0 votes
1 answer
199 views

HighTotal not showing up in /proc/meminfo

I'm trying to evaluate what is the peak memory of a program (in a docker image). I'm running cat proc/meminfo at the end but I don't see HighTotal, any idea why is that? (using docker's debian:latest)...
Thomas's user avatar
  • 903
0 votes
1 answer
1k views

MemAvailable higher than expected

$ free -h total used free shared buff/cache available Mem: 7.7Gi 4.5Gi 692Mi 305Mi 2.5Gi 2.6Gi Swap: 2.0Gi ...
sourcejedi's user avatar
  • 50.8k
11 votes
2 answers
4k views

Is "Cached" memory de-facto free?

When running cat /proc/meminfo, you get these 3 values at the top: MemTotal: 6291456 kB MemFree: 4038976 kB Cached: 1477948 kB As far as I know, the "Cached" value is disk ...
Roland Seuhs's user avatar
0 votes
1 answer
1k views

What does ShmemHugePages mean?

I'm using grep Huge /proc/meminfo and getting: AnonHugePages: 16384 kB ShmemHugePages: 0 kB HugePages_Total: 33 HugePages_Free: 18 HugePages_Rsvd: 18 HugePages_Surp: ...
Adrian's user avatar
  • 701
4 votes
1 answer
286 views

different kernels report different amounts of total memory on the same machine

I have two x86_64 kernels compiled on the same machine against the same code (4.15.0 in Linus' source tree). The config files were produced by running make localmodconfig against that source, using ...
grobber's user avatar
  • 59
1 vote
1 answer
3k views

How to find the right memory size?

We have a Linux machine with 32G. We capture the mem as follows: mem=` cat /proc/meminfo | grep MemTotal | awk '{print $2}' ` echo $mem 32767184 and now we convert it to GIGA: mem_in_giga=` echo $(( ...
yael's user avatar
  • 13.3k
5 votes
1 answer
6k views

How are /proc/meminfo values calculated?

/!\ Current state: Update 4 /!\ Some /proc/meminfo values are a sum or a difference of some other values. However, not much is said about how they are calculated in these two links (just do ctrl-f ...
X.LINK's user avatar
  • 1,334
2 votes
1 answer
12k views

How to troubleshoot what eats memory?

I'm trying to figure out why memory consumption started to constantly increase on my server during the last hours. I've tried to find the cause on the application level, but no success. That is why ...
Y. E.'s user avatar
  • 123
15 votes
2 answers
16k views

How can I get the amount of available memory portably across distributions?

The standard files/tools that report memory seem to have different formats on different Linux distributions. For example, on Arch and Ubuntu. Arch $ free total used free ...
terdon's user avatar
  • 243k
6 votes
1 answer
2k views

Recover from faking /proc/meminfo

So, without really thinking too much, I ran this script: #!/bin/bash SWAP="${1:-512}" NEW="$[SWAP*1024]"; TEMP="${NEW//?/ }"; OLD="${TEMP:1}0" sed "/^Swap\(Total\|Free\):/s,$OLD,$NEW," /proc/meminfo &...
Lauri Elias's user avatar
11 votes
1 answer
849 views

What is using 4GB of memory? (Not cache, not a process, not slab, not shm)

We have some EC2 servers that experience a memory leak over days or weeks. Eventually there gets to be many GB of memory that is used (according to tools like free and htop) and, if we don't restart ...
Caleb Spare's user avatar
1 vote
0 answers
154 views

Investigating Active MemInfo

I am seeing high Active usage when I do a cat /proc/meminfo : MemTotal: 65965328 kB MemFree: 51640992 kB Buffers: 1050332 kB Cached: 8516112 kB SwapCached: 0 kB Active: 11512732 kB Inactive: 1878028 ...
Sirish Chandraa's user avatar
3 votes
0 answers
335 views

In meminfo, sometimes Mapped more than Cached

In /proc/meminfo, AFAIK Cached >= Mapped But after /proc/sys/vm/drop_caches, it goes to Cached < Mapped Cached: 66132 kB Mapped: 67792 kB /proc/meminfo contents ...
Hwangho Kim's user avatar
4 votes
1 answer
4k views

When is swap triggered or how to calculate swap_tendency?

I'm trying to use Redis for production services and trying to avoiding swapping, which is bad for performance. I had learn that swap is triggered by swap_tendency which is depending on ...
Zhuo.M's user avatar
  • 143
300 votes
9 answers
446k views

How to display meminfo in megabytes in top?

Sometimes it is not comfortable to see meminfo in kilobytes when you have several gigs of RAM. In Linux, it looks like: And here is how it looks in Mac OS X: Is there a way to display meminfo in ...
Anthony Ananich's user avatar