Swap space is an area of the hard disk that serves as an overflow when the computer memory is full. The memory used by inactive applications is partially written out to disk to make room for other applications and for the disk cache for active files.

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Calculating RAM/Swap Space Requirements [duplicate]

I have been developing a MySQL database that makes some use of BLObs. This has now been transferred on to a virtual machine (VM) in preparation for going fully into the 'cloud'. However some of the ...
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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 ...
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How do I know I should turn swappiness down?

I have 5.5 GiB memory, using 2.8 GiB (~50%), but my swap is using 1.9 GiB of 5.6 GiB (~33%). My computer operates okay but is sluggish at times. So is this a high amount of swap usage or completely ...
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Can swapping be disabled on the application level?

I'm currently using thunderbird with gnupg to read encrypted emails. If I understand the swapping behavior correctly, the memory pages containing the decrypted emails might be swapped out and leave ...
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how partition for OpenSuSE dual-boot

Currently I'm running Ubuntu 14.10 and have quite a bit of free space on this disc: thufir@doge:~$ thufir@doge:~$ sudo fdisk -l Disk /dev/sda: 465.8 GiB, 500107862016 bytes, 976773168 sectors ...
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Java process gets killed frequently by OOM - Killer on upgraded hardware

I am running solr on an Ubuntu server along with 4 other java processes. Current index size is 30 GB. My solr process gets killed frequently in few hours. It clearly mentions that its an OOM killer. I ...
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Delete a swap partition without user interaction

I have a VM with a swap partition on /dev/sda5. The problem is fdisk is interactive so I cannot use it to delete a partition without user interaction. How do I delete the partition in my ...
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33 views

Same Swap Partition in Multi Boot [closed]

I have a Macbook Pro with 256 GB of space and 8GB of RAM. and I want to make a multi boot like: Mac OS X 120 GB Windows 8.1 30 GB Ubuntu 14.04.1 30 GB Debian 7.7 25GB Arch Linux 15 GB COMMON ...
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ZFS swap vdev space accounting

I am on an OpenSolaris system with ZFS on it. I am trying to determine the exact space usage and/or reserved space for the swap vdev. root@storage:~# zfs list NAME USED AVAIL ...
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What NOT to put on an SSD?

I bought an SSD and I am going to set up my desktop system with a completely fresh Linux installation. SSDs are known to be fast, but they have a disadvantage: The number of writes (per block?) is ...
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specific swap partitions for multiple debian instances in a single computer

I'm trying to setup a computer with three debian instances (wheezy, jessie and sid), I've created / and swap partitions for each debian instance, during the installation I did specify which swap ...
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154 views

When does swap start to be used? When does a process get an out of memory error and be killed?

When does swap start to be used? Is it when the memory is fully used? Or when the memory hasn't been fully used? When does a process get an "Out of memory" error and be killed by the kernel? is it ...
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Does a Linux server use swap space of an SSH client? [closed]

I currently am SSHing into a Linux server via my mac's terminal program. Afterwards, I run whatever simulations and calculations I need to do. However, I noticed that after I log in, it says on the ...
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swap partition and its laws

I remember for choice of swap partition, we should use (swap > 2xRAM) at least.Of course it deprecated , because max of computer's ram is very high. kernel support it. My question: i remember each ...
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How can swapoff be that slow?

Somehow I happened to swap out 14 GB of memory. After having killed the culprit, I have tons of free memory again, so I thought I could bring in the important data again. So with 5 GB out of 32 GB ...
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Detect whether a swap partition is in use by a hibernated system

Is there a way to detect whether a swap partition contains the memory of a hibernated system? More specifically: suppose I have a Linux installation and that I hibernate it. This means that all the ...
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Are there any side effects when two distros share a swap partition?

In order to save disk space, I want to have two OS installations share a single swap partition (a dual-boot). Is this a good idea?
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Why is my computer sluggish after downloading a lot?

When I download a lot of data (e.g. 3GB) in one go, using a program such as Transmission or Wget, progressively during the downloading, and after it has has finished, the computer always seems ...
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77 views

What is the difference between MAC OS X “Virtual Memory” and Linux/Unix Swap? [duplicate]

I would like to understand the difference of MAC OS X "Virtual Memory" and Linux/Unix Swap. I ask this because I observed that MAC OS X "Virtual Memory" seems to work way more efficient (in desktop ...
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unlimited tmpfs

How to have the advantages of tmpfs and not be limited to its small size? I'm thinking of a shell script that runs as a daemon, monitors RAM and adds more swap files in specified folder, when memory ...
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107 views

OpenBSD runs out of memory, while not using swap space

I'm working with a fresh install of OpenBSD (5.6 amd64). I'm attempting to build Boost libraries, and quite a few compilations are failing with cc1plus running out of memory errors. I've read ...
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58 views

When the RAM is used up, what will happen?

When I ran ImageMagick's convert to convert and combine image files into a pdf file, it will create 10GB temporary dirs and files in /tmp. I am not sure if it did that all the time, or because my ...
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566 views

Diagnose high swap usage on AIX

Which would be the best approach to diagnose high SWAP usage on an IBM AIX 6.3 machine? I've already tried with lsps -a and lslv. But also I'm looking for a strong scenario, like using topas. Any ...
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523 views

Swap space not used

I recently installed Debian 6.0.6. Here are the machine's states: CPU - AMD XP 3000+ RAM - 1 Gig HDD - IDE 80 Gig I primarily use this machine for developing toy personal projects. When I run ...
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Effects of SWAP failure

A team member has created a swapfile on one of our machines which needed more swap. And he created it on a filesystem on SSD. While our servers are not swapping a lot and probably safe to keep the ...
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Http taking all swap [closed]

I have a dedicated server running centos&cpanel with 2 GB of ram where I host several websites. All are wordpress + 1 opencart. Every 2 days or so the swap memory get consumed and server load ...
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111 views

Opening files of size larger than RAM, no swap used.

I found myself asking this question while doing small experiments and reading upon how memory is managed in Linux. I have a 64-bit Centos 6.5 machine with 512M RAM and 1G SWAP. I created a 1GB file ...
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139 views

Why does mouse and keyboard freeze when Linux swaps

I have noticed that under Linux, when there is heavy swapping, the mouse cursor freezes, and even CapsLock or Ctrl+Alt+F1 don't work. The system uses the deadline I/O scheduler but this should not ...
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Does the debian setup with lvm also encrypt the swap partition?

I'm planning a fresh debian install on my notebook and want to have full disk encryption. But I mainly hibernate, which is why I want my swap to be encrypted as well. During the graphical expert ...
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Why adding swap space is the slowest part of the booting process? [closed]

I'm not having performance problems, but just running dmesg command, I can see that adding Swap space is the slowest part of the booting process. Why? I actually have ~4GB for swap and 2GB RAM ...
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54 views

Why do I need mkswap if swap space has been created via fdisk?

I created a partition called /dev/sda3 as a swap partition, and changed the ID to 82 (Linux Swap) via fdisk. If this partition was recognized as a swap partition (seen in the output of fdisk -l and ...
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112 views

What's the pros and cons of disabling the swap partition if the RAM is large enough? [duplicate]

My computer has 16GB RAM and 1TB SSD. So I think the swap partition is not needful. What's the pros and cons of disabling the swap partition if the RAM is large enough? Is it recommended to disable ...
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Luks Partition Mounting After Removing From fstab

I have 3 encrypted partitions, one for /, one for /home, and one for swap. It seemed silly to me to type in my password 3 times, so I replaced the swap partition with a swap file on the encrypted ...
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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 ...
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Is swap an anachronism?

I've used unix for quite a while, and for the last couple years I've felt like swap is an anachronism, but I'd be curious what other folks think. My argument is roughly this (assuming no global ...
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Why use swap when there is more than enough free space in RAM?

Using swap space instead of RAM can drastically slow down a PC. So why, when I have more than enough RAM available, does my Linux system (Arch) use the swap? Checkout my conky output below: Also, ...
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full disk encryption (including swap, possibly plausible deniability as well)

I'm looking for a method to encrypt my laptop including the swap partition. I also read trough older similar questions but mostly the answer included just a what not much of a how. (Currently I'm ...
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What happens when a tmpfs is full and no swap space is available?

Let's say I have a setup with 16 GB of physical RAM, A tmpfs of max. 8 GB containing a file with 5 GB and A swap sized 4 GB. If I'd try to, e.g., create a copy of the 5 GB file on the tmpfs, what ...
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Swap appears to not be in use

(I am currently using Ubuntu 14.04 LTS, GNOME environment) tl;dr How can I force more memory swapping (swappiness already at 100)? I have recently been experiencing a lot of system freezes/crashes. ...
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slow Matlab on Ubuntu LTS and ZERO Swap

I was using Matlab2012 under Win7 and my algorithm was consuming a huge amount of memory though it was fast (80 seconds for one iteration). Now I am using Matlab2013 under Ubuntu 12.04 LTS and though ...
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Is there anything in RHEL 6.5 that would affect I/O speed for something <24K vs >24K?

Generally, transactions for my app of setting and getting data internally are measured in a couple of millis. However, over 24K in size, that time can jump to just over 100 millis. Is there anything ...
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Fastest and Safest way to increase Swap Space on Scientific Linux

Memory Swap Ratio Company System Today, a monitoring system indicated that one of the systems in the company has run out of memory. Executing htop on this system indicated that the Memory was nearly ...
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280 views

How to enable swap accounting for memory cgroup in Archlinux?

On my Archlinux box I want to limit some applications to a smaller amount of memory using cgroups. Since I use swap, I need to account memory+swap. How can I enable swap accounting?
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How to make files inside TMPFS more likely to swap

I'm using tmpfs for my /tmp directory. How can I make the computer decide to swap out the files inside the /tmp before swapping out anything that is being used by applications? Basically the files ...
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What does the vm.swappiness parameter really control?

Per the kernel documentation: This control is used to define how aggressive the kernel will swap memory pages. Higher values will increase aggressiveness, lower values decrease the amount of swap. ...
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How much RAM needed for preventing use swap?

At my system always available some "Free" and "Inactive" memory, but sometimes system move couple megabytes to swap. Per night it maybe around 100MB, but for a few days in swap could be more than ...
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Why is my swap not being activated automatically via fstab?

I've got a Linux embedded system that I'm experimenting with (the Elektor Embedded Linux Made Easy board, based on the GNUBLIN http://en.gnublin.org/index.php/GNUBLIN-Elektor). I'm using the 3.3 ...
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kswapd0 takes 99% to 100% CPU in RHEL 6.3

I have 5 systems on which I have just installed RHEL6. System configuration is CPU-i7 HDD-500 GB RAM-2 GB Swap- 4 GB I have installed the same software's and all the configuration as per ...
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997 views

Swap partition in LVM?

I was wondering if putting the swap partition into a logical volume group has any drawbacks (e.g. performance), or would it be "just the same" as having it as a separate primary/logical partition? I ...
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Extending swap on Centos

I recently created a swap file on my centos 6 based VPS using this guide. Now I wanted to extend this swap and I was reading through this guide. However, I think I've created a swap file than a ...