The ram tag has no wiki summary.
1
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1answer
40 views
file access time after loading file into the cache
I read from here that I could load file into RAM for faster accessing using the below command.
cat filename > /dev/null
However, I wanted to test if the above statement is really true. So, I ...
0
votes
0answers
20 views
How fast is a process reading/writting virtual memory?
So, we have top, htop, iotop, iostat, vmstat, etc, to measure many different things on Linux, but how can one measure how much MB/s a process is reading and writting to/from RAM, i.e., virtual memory?
...
5
votes
1answer
73 views
Where has my RAM gone & how to interpret atop's memory output?
For a while, I encounter RAM-shortages on my Debian webserver (VPS/virtual machine). This would not be unusual, if they happend on a regular basis. But they do not. Here's a chart from Munin:
...
2
votes
1answer
39 views
Memory Usage in Linux [duplicate]
How to setup limit for process to memory usage?
Similar to open files limit in /etc/security/limits.conf:
ubuntu soft nofile 4096
ubuntu hard nofile 8192
...
-2
votes
0answers
17 views
Linux (Xubuntu) ram and cpu usage [duplicate]
I'd like to know if Linux is able to see and use all available ram and cpu.
The reason why i ask is because in my Macbook for example i can not add more ram because it can read and use just 2GB, it is ...
0
votes
1answer
37 views
What dev folder allows you tell the OS to cache something?
Someone told me that there is a sub folder off of dev that basically allows you to tell the OS to keep the contents of that folder cached in RAM. So if I put some files & directories in ...
0
votes
1answer
49 views
Arch linux weird ram issues
I installed Arch linux (I have reinstalled it a couple of times, actually, in the past 3 months, just to get to know it better).
My problem is, that I have 4GB RAM, and as soon as my free RAM hits ...
1
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2answers
92 views
Why does Linux only see 3832MB of my 4096MB of RAM?
I am setting up a lot of 64-bit RedHat VMs (VMware vSphere) for our development department in my company. Most of them start with 4096MB of RAM, but Linux only seems to recognize 3832MB. Can anyone ...
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0answers
16 views
how to find where buffers/cache are and how to clean them up? [duplicate]
I want to create 20gb ram disk for ANSYS to work in yet on free -g I see:
And personally I have not created any ram drives yet. So I wonder how to maximize avaliable ram: how to locate what is using ...
0
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1answer
25 views
Virtualbox delete vm ram
If I delete a VM in VirtualBox, what happens with the RAM I used to create that VM? Is it freed?
0
votes
1answer
286 views
How to reduce chrome's virtual memory usage?
I am running a Debian Jessie and having memory issues when using Google Chrome
I tried disabling extensions, disabling cache, flushing the cache, and disabling the web 3d rendering, but nothing ...
3
votes
2answers
258 views
How to tell whether RAM ECC is working?
I'm planning on getting some ECC RAM to replace the non-ECC RAM I currently have installed on my Asus M5A97 Pro motherboard (AMD 970 chipset, FX-6100 CPU).
After I install the RAM, how do I tell ...
0
votes
1answer
71 views
should I reduce /dev/shm size?
I have a server wity 8 GB RAM
Mem:
Total 8031464
Used 5146344
Free 2885120
If I execute
# df
it always returns this
tmpfs 4015732 0 4015732 0% /dev/shm
What does it ...
1
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0answers
54 views
Swap on video ram in a VM
I have a very small VM running in a cloud with only 512 MB ram. I read, it is possible to use the video card as swap as descriped here:
Graphics cards contain a lot of very fast RAM, typically ...
1
vote
1answer
43 views
Compress memory on low Ram VM
Is there a way to get out more out of your limited Ram on a VM?
I have a VM running on a cloud hoster and try to optimize a quite low on RAM mashine.
I heard, there is a way to compress parts in the ...
4
votes
1answer
126 views
Does tmpfs automatically resize when the amount RAM changes, and does it compete when there's multiple tmpfs?
If I have a tmpfs set to 50%, and later on I add or remove RAM, does tmpfs automatically adjust its partition size?
Also what if I have multiple tmpfs each set at 50%. Do multiple tmpfs compete ...
4
votes
2answers
112 views
1GB huge page - Is writing occurring in 1GB chunks?
I'm trying to understand the relation between huge page size and how data is actually being written to RAM.
What happens when a process uses a 1GB huge page - does writing occur in 1GB chunks? I ...
1
vote
0answers
75 views
Xeon Phi swap from host's tmpfs
I want to use swap on Xeon Phi (mic0) using RAM from the host
On the host:
# free -m
total used free shared buffers cached
Mem: 129022 60312 ...
1
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0answers
59 views
EDAC (Error Detection And Correction) infrastructure in linux kernel
I am wondering how I can make use of the EDAC infrastructure in linux kernel. I have a i7-4600M CPU and I have compiled EDAC as a module in my kernel:
--- EDAC (Error Detection And Correction) ...
0
votes
1answer
69 views
Take copy of RAM
How trivial is it to take a copy of the current state of a Live Linux Distro's RAM storage?
I have had situations where it might be useful to debug what caused a problem with the OS, and if I had ...
2
votes
2answers
87 views
Tool to force use FILE instead of RAM
I'm wondering why there is no such tool like ram2swap, similar to cpulimit in parts.
E.g.
There is program daemon.bin.
Let's create temporary swap file ( 1 Gb ):
% dd if=/dev/zero of=tmp.swap ...
3
votes
1answer
70 views
How to limit a user's RAM on Ubuntu? [duplicate]
I currently have a "friend" that has an account on my dedicated server which is running Ubuntu. Not getting into specifics, but he said he will use ~2gb max and he's using ~10gb. On to the question. ...
1
vote
1answer
49 views
CPU and RAM monitorization by parent id
I'm trying to monitor the CPU and RAM usage (in % of total for example) of a given process wich may spawn several processes. The parent process is /bin/rscw so I get its pid by
ppid_bl=$(ps -ef | ...
6
votes
1answer
193 views
How to have Linux wipe/randomize/sanitize RAM at shutdown?
For mysterious reasons I still double boot sometimes into Windows.
My problem is that I fear that information may leak because the RAM memory is accessible to Windows. (the Linux partitions are ...
1
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0answers
102 views
Second RAM module is not shown in `free` in Manjaro
I have two RAM modules (8 GB each) but there is only one shown in free. I hope that following info will help you to locate the problem and find a solution:
$ uname -srvmo
Linux 3.10.27-1-MANJARO #1 ...
1
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0answers
140 views
weird problem with 64 bit install and memory
I have a laptop with 8gb of RAM in two 4Gb slots, the processor is 64 bit compatible. However when I try to install 64 bit version of Linux (I tried, mint, arch, manjaro), it refuses to load the ...
14
votes
1answer
1k 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 ...
0
votes
1answer
324 views
swappiness and RAM usage
Been going through this topic - http://askubuntu.com/questions/157793/why-is-swap-being-used-even-though-i-have-plenty-of-free-ram.
Turned down swappiness to 10 and then to 0 but my installation is ...
0
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0answers
25 views
Limit CPU/RAM usage per user? [duplicate]
I'm running game server applications on dedicated server that I have, but I want to be able to limit the CPU/RAM/etc usage on a per-user basis to make sure one of the servers doesn't eat up more ...
0
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0answers
54 views
Creating a fixed-size post boot block device from ram
First off:
/root# cat /proc/version
Linux version 3.12.6
What I'm trying to do is create a block device (no filesystem) out of ram of a fixed (configurable) size (pre-allocated, not ...
1
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0answers
16 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 ...
5
votes
2answers
365 views
How to create a fixed size Linux ramdisk which does never swap to disk?
I want to create a fixed size Linux ramdisk which never swaps to disk. Note that my question is not "why" I want to do this (let say, for example, that it's for an educative purpose or for research): ...
3
votes
4answers
8k views
Java “Could not reserve enough space for object heap” even though there is enough RAM
I am currently having some issues running Java. It won't start because of heap issues. But I have more than 9 GB Ram free (or even 16 GB if you assumed the cache would be empty). This is the error I ...
0
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3answers
323 views
How much swap space should I use? [closed]
What rules should I follow to determine how much swap space my linux-based computer should have today?
0
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0answers
88 views
What does it mean to redirect /dev/console through a non-existent file?
I have been trying to follow the "NAND firmware update" tutorial and I am perplexed by these last lines:
now, in second stage, all processes are gone, only /dev/console in old
root is still open ...
0
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0answers
33 views
Allocating more than 1 GB DMA memory
Is it possible to allocate more than 1 GB DMA memory on a machine, say with 24 GB RAM? If not, what makes it impossible?
2
votes
1answer
230 views
Issues with grub badram
I have a stick of bad memory (the computer randomly segfaults an it gives memtest86+ errors, picture of output at bottom). As I would like this computer to be working while I work on getting new ram, ...
0
votes
3answers
87 views
How to get data shown out of workspace or directly from application?
Because of some reason I had to use another web browser than my main which I use daily and I chose a small browser which I installed long time ago. This brower is called Dooble, version 0.07 ...
19
votes
3answers
4k views
How much RAM does the kernel use?
This question is motivated by my shock when I discovered that Mac OS X kernel uses 750MB of RAM.
I have been using Linux for 20 years, and I always "knew" that the kernel RAM usage is dwarfed by X ...
10
votes
6answers
2k views
Can Linux “run out of RAM”?
I saw several posts around the web of people apparently complaining about a hosted VPS unexpectedly killing processes because they used too much RAM.
How is this possible? I thought all modern OS' ...
3
votes
1answer
2k views
How to view RAM's SPD / timings table?
In Linux Mint, how to get the same information presented in the lower half of the below picture?
Output by CPU-Z in Windows:
What I've tried:
Running CPU-Z 1.66 in Wine as Windows 95, 98 and XP.
...
1
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0answers
53 views
looking for name of a userspace tool for disk/network caching? [closed]
I remember seeing a blog post a month back that used a tool in the command which acted like a user space caching tool to buffer/cache reads and writes in RAM to overcome disk or network contention. I ...
0
votes
2answers
61 views
Is there kernel patch to prevent load files into RAM for LiveCD?
Is there kernel patch to prevent load files into RAM for LiveCD?
I mean, if I'm use LiveCD with "boot to Ram" option, there is no needs for kernel to load executable binaries to RAM from RAM.
It ...
1
vote
1answer
79 views
External Cache not socketed
When I check my CPU Cache with command dmidecode, I get Cache configuration to be Not Socketed. What does that mean?
prayag@prayag:~/hacker_/draobkcalb$ sudo dmidecode -t cache
# dmidecode 2.11
...
0
votes
1answer
685 views
How to reduce buffers\cache
A monitoring system keeps alerting that my machine is reaching\breaking through it's RAM utilization threshold which is 15 GBs.
I've done some reading and understood that the apparent RAM utilization ...
23
votes
1answer
16k views
How do you empty the buffers and cache on a Linux system?
Prior to doing some benchmarking work how would one free up the memory (RAM) that the Linux Kernel is consuming for its buffers and cache?
5
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1answer
1k views
Does kernel: EDAC MC0: UE page 0x0 point to bad memory, a driver, or something else?
kernel: EDAC MC0: UE page 0x0, offset 0x0, grain 0, row 7, labels ":": i3200 UE
All of a sudden today, our CentOS release 6.4 (Final) system started throwing EDAC errors. I rebooted, and the errors ...
2
votes
3answers
378 views
Memory Mapping Linux 3+ kernel
Can some one help me understand how memory mapping is done
Gone through this
Why does Linux show both more and less memory than I physically have installed?
but still i am not able to understand ...
1
vote
2answers
428 views
RAM size and SWAP size
I want to know why the swap partition have to more double size the RAM Size ? for example if the ram installed in machine 64 G.B , the swap have to be 128 G.B ?
0
votes
1answer
178 views
Converting *.ram to *.avi
I just came across an old file witn a ram extension. I've tried viewing it ( just to see what it is ) and am having extreme difficulties. I've tried looking for spftware online and alll I find are ...
