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 do I make a RAM disk?

I want to make a partition that is made of ram ... Example In windows 7 you can make a partition that is made of ram I have created 1 GB of partition in ram . using Primo RamDisk Is there any ...
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7k views

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 ...
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4answers
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Using usbdrive as ram in ubuntu

In windows it is possible to use usb flash drive as a virtual ram. I wonder if it is possible to do so in ubuntu? If it is, how could one do it? [Edit]: I mean Ready boost equivallent for ubuntu. I ...
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4answers
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Why is the cache in my memory always full?

I have 6GB RAM, i5 2.4GHZ Processor running Ubuntu 11.10. I partitioned my HD so that I have 8GB swap. When streaming online or opening several tabs in Chromium I soon have 4GB Memory in the cache. ...
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3answers
681 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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3answers
47k views

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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3answers
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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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1answer
2k views

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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1answer
3k views

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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1answer
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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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2answers
120 views

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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2answers
10k views

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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4answers
17k views

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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2answers
2k views

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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2answers
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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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2answers
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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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2answers
5k views

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 ...
5
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1answer
5k views

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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2answers
2k views

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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2answers
177 views

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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2answers
541 views

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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2answers
950 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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2answers
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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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1answer
2k views

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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2answers
8k views

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
5k views

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 ...
4
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1answer
2k views

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 ...
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2answers
5k views

How to find how much RAM my computer has

How do I find out how much ram my computer has? I am running Ubuntu 13.04.
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1answer
798 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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1answer
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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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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 ...
4
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2answers
4k views

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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1answer
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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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2answers
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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
2k views

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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2answers
888 views

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 ...
4
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1answer
55 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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2answers
97 views

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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1answer
3k views

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 ...
4
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1answer
212 views

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 ...
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1answer
7k views

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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3answers
783 views

Installed 11.10, but it's not detecting all 8GB of RAM, only 3.9GB. BIOS sees 8GB

Just installed 11.10, but it's not detecting all 8GB of RAM. System Info says there are 3.9GB. Bios doesn't have a problem recognizing all 8. free -m results in: total used ...
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1answer
284 views

Ubuntu gets slower by the day

Ive noticed that Ubuntu has been getting slower and slower to boot, launch programs, etc. I installed 12.04 about 4 months ago,now 12.10, running on a quad-core Q8300 Intel, 4GB Ram, and an 80GB WD ...
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2answers
2k views

large tmpfs /run partition - must it be so big?

I am running Ubuntu 11.10 desktop on a couple of 8G RAM Wintel boxes. Both have been created automatically by the default installer with a 1.6GB tmpfs /run partition, where I suspect this amount of ...
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1answer
374 views

What is the normal metacity and nautilus memory consumption?

uptime 07:07:32 up 13 days, 4:01, 2 users, load average: 0.47, 0.28, 0.21 System Monitor shows that metacity uses 1.2 Gib and Nautilus 450.1 Mib. Everything has gotten pretty slow-ish so I ...
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1answer
5k views

Why doesn't Ubuntu detect all of my RAM on 64-bit? [duplicate]

Possible Duplicate: Ubuntu only detects 3.1 GB of ram on Ubuntu 64 bit ISSUE IDENTIFIED: BIOS bug. See dmesg output below. Question is: How to resolve this? Change made since 2.6.32 have ...
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3answers
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When I have 6 GB of RAM installed, why is just 3 GB available on Ubuntu?

I'm using a laptop with 32-bit Ubuntu 10.04. I used to have only 2 GB of RAM. Today, our IT-support upgraded my laptop to a total of 6 GB of RAM. They told me "Though you do now have 6 GB, when you ...