In computing, memory refers to the state information of a computing system, as it is kept active in some physical structure.
-1
votes
1answer
7 views
How to put temporary load to memory on Unix server manually
I need to do some test on memory ,Please can someone share the script to add temporary memory to Unix system
1
vote
0answers
26 views
About the usage of Memory in a linux server [duplicate]
I find my server's memory usage is so high, part of the output of command free is shown below:
total used free shared buffers cached
Mem: 82446460 81961412 ...
1
vote
1answer
56 views
How to dump memory image from linux system?
I know to dump memory images in Window. (eg-dumpit) But I don't know how to dump memory images in Linux.
I wanna get memory images in Linux and from linux to linux with ssh connection or something.
...
3
votes
1answer
31 views
program executing for 2 days
I have a java program which implements the Hungarian algorithm. I made changes to the existing code in such a way that the input is read from file. I have a pretty huge input around 32,000 rows for ...
7
votes
7answers
815 views
cron Vs. sleep - which is the better one in terms of efficient cpu/memory utilization?
The Case:
I need to run some commands/script at certain intervals of time and for this I have two options - 1. set up a cron-job or, 2. implement a loop with sleep in the script itself.
Question:
...
1
vote
0answers
25 views
Set memory allocation for applications in Ubuntu [duplicate]
I have an application running under Ubuntu that tries to consume all available memory. Is there a way to specify and restrict the allocations available for a given application?
0
votes
0answers
42 views
How to cause memory fragmentation on a Linux based embedded device?
Hardware
ARM
What am I trying to do:
Answer: I am trying to create memory fragmentation on a Linux 2.6.31 based swapless embedded device.
Why:
Answer:I am trying to port some patches to Linux ...
2
votes
0answers
50 views
Why does the kernel boot faster with less memory allocated?
This is not a important question, I'm just curious. Something strange happened, which isn't quiet clear to me:
In the kernel command line, the amount of the memory can be set statically with the ...
4
votes
3answers
80 views
What happens in UNIX/Linux when a program is bigger then size of memory?
I was wondering how embedded systems are able run programs bigger than the size of memory. If I had 1 GB of memory and the program was 1.5 GB, would the program load? Are there systems that only use ...
1
vote
2answers
31 views
Are limits in linux (like those controlled by ulimit or /etc/security/limits.conf) per user or per user per process?
I saw three copies of a process running and one of them cored in what seems like memory issue. Each individually occupies about 3-4 GB of memory..would a limit account for killing one of them? And if ...
16
votes
1answer
981 views
What is maximum RAM supportable by Linux?
What is the maximum supportable RAM by Linux? Assume that hardware is/supports 64-bit. Among all Linux distros.
Does it go up to 16 exabytes, or is it limited like with Windows which I believe is 192 ...
9
votes
1answer
161 views
Loading of shared libraries and RAM usage
I'm wondering about the way Linux manages shared libraries. (actually I'm talking about Maemo Fremantle, a Debian-based distro released in 2009 running on 256MB RAM).
Let's assume we have two ...
3
votes
1answer
59 views
Optimised ZFS in low RAM environment feasibility?
I am currently setting up a file server and have come to the point of actually
setting up the data drives. The system has 4 drives (one OS disk, 3 data
disks). The OS disk is formatted as ext4 and ...
0
votes
1answer
36 views
mdadm large memory consumption [closed]
I am building a RAID 6 with mdadm (8 WD Red 3 Tb) on Ubuntu 13.10x64 server with ext4 filesystem.
When I download torrent on the array, server RAM is filled for maximum cap (8 Gb)
memory is free when ...
1
vote
2answers
75 views
How to remove cache device from bcache?
I believe, that once I made sure my cache device state is "clean":
$ sudo cat /sys/block/bcache0/bcache/state
I can just physically remove it from the machine when it is powered off or boot with ...
1
vote
0answers
42 views
dovecot. Can't allocate memory, but free -m show available memory
I trying to send mail with PHP (engine - Drupal). But it can't send mail and write message about it in to log (nothing more that adressed).
Part of /var/log/mail.err :
Feb 14 19:55:30 hivede13-3220 ...
1
vote
1answer
84 views
How to reduce ClamAV memory usage?
I'm running a Ubuntu based web server (Apache, MySQL) on a 512MB VPS. This is more than sufficient for the website it is running (small forum).
As I wanted to add some protection against viruses I ...
3
votes
3answers
115 views
Why does MemTotal in /proc/meminfo change?
I monitor value from /proc/meminfo file, namely the MemTotal: number. It changes if a ram module breaks, roughly by size of the memory module - this is obvious.
I know the definition for the field ...
0
votes
1answer
42 views
What's exactly Compile time, Load time, and Execution time? [closed]
It's said,
Compile time -- When it is known at compile time where the process will reside, compile time binding is used to generate the absolute code. Here I'm not sure what is the absolute code?
...
0
votes
1answer
12 views
Preventing a new instance of a program to open when calling it
My problem is with FBI (frame buffer image viewer) for Linux, but my question and any answers are perhaps applicable to more than only that program. I don't know. Anyway…
While things are loading on ...
1
vote
0answers
13 views
Amount of memory transfer on a running Linux
Can I determinate the amount of RAM exchange (between the CPU and the RAM) on a running Linux system?
I'm not looking for the max RAM speed (then memtest would be valid answer). I'm looking for the ...
0
votes
1answer
149 views
Java/malloc memory corruption error when running SDK Android Manager
I want to install Android SDK, so I manually installed Java JDK 7u51, downloaded SDK ADT bundle for Linux x64, and tried to run it. When I run android, the SDK manager windows hangs halfway through ...
0
votes
1answer
38 views
Is this method safe or recommended for moving a /home directory?
I have my linux install on a small disk. I want to put the home directory on a different hard-drive. I was thinking of using this and then this. Would this work? Is there a better way? Should I just ...
0
votes
1answer
35 views
Is there something wrong with df output? [duplicate]
I'm using the command df -h to check disk usage on CentOS 6.4. I see an inconsistency with the output.
look at the line Filesystem: total 490Gb, used 55Gb, and Available 411Gb. What is it mean?
I ...
0
votes
2answers
133 views
Memory usage on SunOS and Linux
I have some doubts with memory usage.
Currently I have nagios check who measures used memory from free -m command on Linux. I added another script for memory usage from ...
0
votes
0answers
14 views
How to install memusg tool
I've tried with yum install memusg but returned:
Loaded plugins: fastestmirror, security
Setting up Install Process
No package memusg available
Error: nothing to do
Any solution
4
votes
1answer
62 views
Why do the data and code segments completely overlap in Linux?
Context: I'm reading "Understanding the Linux kernel, 3d ed", which uses the 2.6.11 kernel.
Question: As I understand, the physical address is obtained by translating the linear address, which is ...
1
vote
0answers
30 views
memory consumption alert
My VPS has reported a memory consumption alert says reached 273% and I cannot access any of my sites.
But I checked on the terminal today and it does not look like a memory problem. Am I correct in ...
-2
votes
1answer
52 views
Loading a kernel driver to a specific memory address
How can I load a kernel driver at a specific memory address?
How could it be done with the following methods?
commands/scripts like insmod or modprobe
using C code (not sure if there may exist ...
3
votes
1answer
131 views
Is it possible to find the physical address range of a DIMM?
I note that SMBios Type 20 would help here, but it's optional as of version 2.5 (2006-09-05) pp. 25, L796, and pp. 131, whereas types 16, 17 and 19 are mandatory, but don't quite help.
Physical ...
1
vote
1answer
68 views
Worker MPM or Prefork?
I understand that there is a comparison topic between the two modules but this is different.
I was contacting cPanel support in order to help me freeing up some memory usage on the VPS. They found ...
1
vote
1answer
209 views
Linux empty buffer cache command permission denied
I'm using the following commands to flush cache:
# sync; echo 3 > /proc/sys/vm/drop_caches
# sync; echo 2 > /proc/sys/vm/drop_caches
# sync; echo 1 > /proc/sys/vm/drop_caches
When I use ...
2
votes
2answers
42 views
Securely viewing an encrypted file
I have a file that is gpg encrypted. I would like to view the content of the file, but leave no trace of the output. Lets say for example that the encrypted file has some passwords, and I don't want ...
1
vote
1answer
90 views
How to see buffered and cached data
~$ free
total used free shared buffers cached
Mem: 3891076 1044972 2846104 0 82744 463876
-/+ buffers/cache: 498352 3392724
...
2
votes
3answers
72 views
How can I find the amount of memory consumed by a process?
How can I find the amount of main memory consumed by a process using ps aux?
I have a process which runs for half an hour. Is it possible to find the maximum amount of main memory consumed by it ...
6
votes
3answers
876 views
How to display meminfo in megabytes in top?
Sometimes it is not comfortable to see meminfo in kilobytes while you have several gigs of RAM. In Linux it looks like that:
And here is how it looks in Mac OS X:
Is there a way to display ...
5
votes
1answer
134 views
The meaning of output of pmap
I wrote main.c in Linux:
int main()
{
while (1){}
}
When I compile and start it, I can pmap it:
# pmap 28578
28578: ./a.out
0000000000400000 4K r-x-- /root/a.out
0000000000600000 4K ...
0
votes
1answer
30 views
HDD indicator blinks when I run out of memory, but I have no swap configured [duplicate]
I'm running Arch Linux, with 8 GB memory and no swap defined.
Sometimes it ran out of memory, then my system get a little bit stuck, and I can see the HDD indicator blinking. Then I restart X, which ...
2
votes
2answers
48 views
Linux-swap on reboot
I'm wondering what actually happens to a Linux-swap partition reboot. I've been taking a course in computer organization and while installing/partitioning a new drive I became rather curious about ...
0
votes
1answer
43 views
How to create memory-based disk in linux? [duplicate]
I need to have a very fast disk for keeping cache. How can I do that in Linux?
1
vote
1answer
62 views
Limiting processes by memory under Linux
We must launch several hungry processes on a Linux system. These processes often need several Go (~5Go) of memory to run (total memory: 16Go RAM + 2Go swap).
At first, when the system was running ...
1
vote
0answers
123 views
CentOS memory allocation
I was running my VPS with CentOS on 1G memory, but I saw the memory was getting "full" so I had 1G extra installed.
This VPS is one I rent at a hosting company.
That company did most of the ...
2
votes
0answers
72 views
Writing to Arbitrary Memory Addresses [closed]
I'm reading "Art of Exploitation 2nd Ed." and I have a question regarding a section on format string attacks.
Target program
Below code (fmt_vuln.c) is a target program.
#include <stdio.h>
...
1
vote
2answers
157 views
Swap bash script pins htop's memory usage
I deployed a hack to add swap space to a VPS that otherwise didn't allow me to use swapon to create a file.
Prior to adding and executing the script, I followed the steps outlined here. and ...
69
votes
12answers
25k views
How to fill 90% of the free memory?
I want to do some low-resources testing and for that I need to have 90% of the free memory full.
How can I do this on a *nix system?
2
votes
2answers
107 views
lsof - debug the output information
I was going through the questions of this site. In this particular question, I see the command lsof being used to list the files that are open for a particular user. I ran the below command in my ...
4
votes
1answer
93 views
Spike in swap utilisation without high swap rate
Every Saturday, for reasons unknown to me, one of my servers experiences a spike in swap utilisation. It's not necessarily a problem as there is plenty of free memory available, but I'd still like to ...
2
votes
1answer
129 views
Know when a memory address is aligned or unaligned
Im getting kernel oops because ppp driver is trying to access to unaligned address (there is a pointer pointing to unaligned address). Im not sure about the meaning of unaligned address. It means not ...
2
votes
2answers
115 views
How does a process handle the situation when it finds no memory to use?
What happens when a particular process finds that there is no memory to use?
Will that process kill/restart another process to proceed their task ?
Or what the process (that requires more memory) ...
0
votes
1answer
60 views
Running git with higher memory allocation
I am facing memory/data segment issues while running git. However, if I set my ulimits to a bit higher like below.
ulimit -m 262144
ulimit -d 262144
It runs fine. Don't we have anyway to allocate ...
