Random-access memory (RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order with a worst case performance of constant time.

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How much ram is being used on my laptop?

I have 3987MB of RAM on my laptop. Task (System) Manager says that I am using 700MB of this RAM, whilst the command "free -m" says I am using nearly 1500MB. Which one is correct and why do they show ...
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How to configure how much RAM usage should to start swapping on Ubuntu

I always notice that Ubuntu start using swap, as soon as the RAM usage is around 60-70%. How to configure it so it should wait so RAM usage became 80-90%. And is there a way to empty the swap, as soon ...
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2answers
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“kernel panic not syncing out of memory and no killable process”

I'm installing Ubuntu Server 10.04 on a Pentium 3 with 256 MB RAM, I select install, continue with the process and when I see the "configuring apt sources" progress bar then I got the error: "kernel ...
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In regards to memory usage, what are buffers?

Just took a look at the memory usage (with free -m) on one of my Ubuntu servers and saw this: total used free shared buffers cached Mem: 751 624 ...
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Ubuntu 12.04 LTS 32bit does not detect 4Gb ram

I have recently installed 4Gb of ram for an existing 12.04 32bit Ubuntu. It's not being recognised, only 3.2Gb is showing, See: administrator@Root2:~$ free total used free ...
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Check the amount of RAM on the server

Is there a way to check a server (without opening it up and physically looking) at the amount of ram that is in the box in terms of how many slots are free. Also I need to know how much ram it could ...
6
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3answers
818 views

How does landscape calculate memory usage?

I'm trying to debug an OOM situation in an Ubuntu 12.04 server, and looking at the Memory graphs in Landscape, I noticed that there wasn't any serious memory usage spike. Then I looked at the output ...
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How do I know which RAM I'm using?

I want to buy some extra RAM but Hardinfo wont tell me which brand, model, latency and speed I'm currently using to buy the same kind. What else can I use?
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tmpfs vs. ext4 ramdisk

I would like to know which of both is faster; a tmpfs or a ext4 ramdisk. If someone knows a good way to benchmark disk perfomance on ubuntu, I will gladly do the test myself and post the results. ...
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MicroSD card is set to Read-only state. How can I write data on it?

I have a MicroSD card reader in my notebook. When I insert a MicroSD memory card into it, I can't write any data on it - it's read-only. The same thing happens when I try to do it under root. And I ...
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1answer
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How can I restore the activity monitor? [duplicate]

Possible Duplicate: What can replace system monitoring in the top Gnome Panel in Unity? I was wondering if its still possible to get the Activity Monitor for things like load and ram usage ...
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What can I move to RAM drive to have the system working faster?

Which files/directories can I move to RAM drive to have the system working faster? I'm planning to upgrade my laptop's memory to 8GB soon, so I'll have some fast memory to use. How to configure the ...
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Only 3.2 Gb of memory being used on a 64-bit system

I have ubuntu 11.10 64 bit: Linux 3.0.0-12-generic #20-Ubuntu SMP Fri Oct 7 14:56:25 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux I have installed 4 Gb of RAM: $ sudo dmidecode --type 17 | grep -E ...
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How large of a swap partition is needed to hibernate?

I've read this question, but it doesn't definitively answer my question. If I want my computer to be able to hibernate, do I need to have a swap partition as large as my RAM, or will Ubuntu wisely be ...
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How to make ubuntu use more RAM?

After 2 weeks of trying, failing, trying again, still failing, I finally got Ubuntu stable and operational. My hard disk is quite old and slow but I have excessive RAM (16 GB 2133 mhz), so I was ...
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Exclude bad ram bytes

I have 5 bytes (or bits, don't know) of bad Ram. How can I exclude these bytes so my Ubuntu 11.10 don't use them. My PC randomly freez, and when I ran memtest it reported 5 errors.
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How much RAM is this application using?

If I run top -c or htop I get processes with their memory consumption, but it is not what I want to see. Is there a command line that allows to see the RAM consumption of a given application ? For ...
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fork: Cannot allocate memory

I am frequently getting: fork: Cannot allocate memory when running commands over ssh. I have 4 GB of RAM and usually 2 GB free. This started happening since I upgraded to Ubuntu 11.10. I then need ...
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Why runs evolution-calendar-factory?

Why runs evolution-calendar-factory? Here are some processes (created with ps aux --forest) lightdm \_ /usr/bin/X -core :0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch \_ lightdm ...
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How to impove Ubuntu performance on netbook

Most recent Ubuntu 12.04 seems to be quite nice and Unity (3D/2D) works fine for me, however not on my old Acer Aspire One any more. There was a times, when I switched from Windows XP to Ubuntu and ...
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3answers
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How to check for errors in RAM via linux?

I have ubuntu 11 running off a 3.6gb usb flash/stick drive. System has 4gb ram and blank harddisk (wiped using DBAN tool). How do i check if there are no errors in my RAM ? Is there a guaranteed way ...
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11.10 x86 - memory RAM problem (shows 3.4 GB when 8 GB are installed)

I recently installed Ubuntu 11.10 x86 on a new computer that has 2 x 4 GB RAM installed (8 GB total). But when I go to the Ubuntu system monitor it only shows 3.4 GB of memory (and ...
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How can I measure how much RAM has been used by a command

I'm trying to measure the memory of a process that I call via the command line (i.e., I want to find out much RAM it takes to for the process ). Is there any command that I can add to the command ...
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Automatically kill a process if it exceeds a given amount of RAM

I work on large-scale datasets. When testing new software, a script will sometimes sneak up on me, quickly grab all available RAM, and render my desktop unusable. I'd like a way to set a RAM limit ...
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zram vs zswap vs zcache Ultimate guide: when to use which one

What the hell are they? how are they different (I've written my understanding in an answer below) In the Zswap system, when a page is evicted from the zswap to the actual swap is it stored in a ...
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Memtest86: Has my RAM gone bad?

I did a memory test with memtest86 on boot, and I'm seeing this: Is my RAM defective? PS : My Ubuntu PC doesn't boot. Shows options in GRUB and then says there are errors in / and failed loading ...
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1answer
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How to give more RAM to wine Applications

Hi I think my system is not allocating enough RAM to WINE applications . I am using WINE to play games but they are loading slowly and RAM usage is normal. So how can I improve reserve memory of WINE? ...
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How to wipe RAM on shutdown (prevent Cold Boot Attacks)?

My system is encrypted using Full Disk Encryption, i.e. everything except /boot is encrypted using dmcrypt/luks. I am concerned about Cold Boot Attacks. Prior work: ...
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1answer
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how to get graphics card memory info? windows and linux shows different value

In my Windows 8, video card shows 640 MB of available memory (Screen Resolution > Advanced Settings or with dxdiag). But ubuntu (with lspci command) shows 256 MB. so who's right?
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Is hypermemory available?

I have a Radeon HD 4550 which supports up to 512 MB of shared memory. When I open the catalyst panel, in the information tab I see that my video memory is only 128 MB which is the base memory or the ...
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How can I make an existing persistant live USB installation load more of the OS to RAM?

A while back I installed (a permanent installation, not a Live USB) Ubuntu on my USB thumb drive. Unfortunately, the transfer rates are too slow for a smooth and responsive experience, so I'd like to ...
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How do I check ram latency?

I need to buy new RAM . First I need to know speed >> done Second I need to know latency >> how ? All I tried from google. dmidecode --type memory dmidecode 2.11 dd if=/dev/zero of=/dev/sda2 ...
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Slow Resume After suspend having chrome running with many tabs

I usually use chrome and Firefox for browsing. I also open many tabs (around 40 in both some times). The problem I have occurs when I resume the PC after having suspended it: It takes from 2 to 5 ...
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992 views

OS only reports 4.1GB of RAM and not the 6GB that is installed… why?

My ubuntu 64-bit 11.10 installed box has 6GB RAM but Ubuntu only uses 4.1GB. I have read various things about the 4GB limit etc, but all those talk about using less than 4GB. What could be causing ...
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Ubuntu Memory Test

Several months ago I was having issues with a Windows PC. I booted from and Ubuntu CD, performed a memory test, and found that I had some bad RAM. I'm having some issues with another PC, so I ...
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1answer
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Good way to run Java and Eclipse from a ramdisk

It is often suggested to me that to improve the performance of the Eclipse development environment, that I should move the Java JDK/JVM (and possibly Eclipse) to a Ramdisk. I know that the Ubuntu has ...
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How to increase the disk space of an Ubuntu VMWare guest, without the cd?

I powered off the VM and on the VMware side increased the allocated disk space. I did this by Edit Virtual Machine Settings -> Hard Disk -> Utilities and so forth. It then warned me that I should ...
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Will adding more RAM increase my computer's performance?

I am looking to increase my computer's performance. Will upgrading my RAM by 12GB or upgrading to a 7,200 RPM Hard Drive increase my computer's performance more? I can only do one, which one will make ...
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1answer
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What Does Cached Memory Mean when Viewing htop?

While viewing the reports of htop, I would like to know what the orange/brown 'cached memory' bars actually indicate. Really I'm looking for a more practical explanation of what I'm looking at, rather ...
4
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1answer
857 views

Max ram for computer 16GB or 8GB

Manufacturer's specifications for my notebook say memory can be extended from 4GB to 8GB. Whereas, running sudo dmidecode suggests the computer can use 16GB as below: Handle 0x0037, DMI type 16, 15 ...
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How can I check how much space there is left on WUBI versus how much space it takes on my HDD?

Using 11.10 for the record. It would be easiest to do it on the Terminal.
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Change swap memory size after adding RAM?

I ordered some addon RAM a few days ago to install on my Ubuntu 10.10 stationary computer and while giving it some thought, I remember that I previously did change the SWAP memory file size on a XP ...
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How to use a compressed ramdisk (ramzswap)? Huge speed gain

Since I don't use my laptop's CD-drive I want to put a small (8 GB) SSD into the CD-drive slot (I'll use a caddy similar to this one). I want to use compressed btrfs on the SSD and put all the data on ...
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Moving files to /dev/shm ramdisk doesn't increase RAM usage?

I've been wanting to make us of a ramdisk on my Ubuntu system for a while, and have done a bit of reading online. Most of the advice centres around using /dev/shm to move files into RAM. I wanted to ...
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362 views

How to set a memory limit for a specific process?

I tried to execute mpiexec -16 ... on a 384 GB RAM server, but it induced OOM Killer and was aborted. How can I set a memory limit for mpiexec execution? I know ulimit, but it might affect other ...
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Unsure if my RAM speed is set correctly

edit: Thank you for reopening I have an an AMD APU as my CPU/GPU (specs below) and its graphical performance benefits greatly from higher speed RAM. In my motherboard BIOS I have set the memory clock ...
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laptop crashed: why? [closed]

my linux (ubuntu 12.04) laptop crashed, and I am trying to figure out why. # last sds pts/4 :0 Tue Sep 4 10:01 still logged in sds pts/3 :0 ...
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2 GB Ram, but Ubuntu runs slowly and hangs if doing too much

I think my system more than meets the minimum/recommended requirements for Ubuntu, but its still running slowly. Especially when I try to multitask by having 4-6 windows open, then it becomes quite ...
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1answer
214 views

How to prevent my system from becoming unresponsive when thrashing (out of RAM)?

I have 8GB of RAM, but sometimes I'm running a couple VMs and enough Chrome processes to use up most of my memory. That's usually fine, but sometimes my system starts thrashing, and it's difficult ...
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245 MB RAM are detected instead of 8 GB Ubuntu 64 bits

I run free -m and I got 245 MB of available RAM while I have 8 GB ! My BIOS detects 8 GB ! What can I do to 'recover back the RAM space ? free -m outputs this: total used ...