Swap space is a virtual memory of RAM. It is used when the amount of RAM is full. Swap space can be a dedicated swap partition, a swap file, or a combination of swap partitions and swap files.

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Prevent important OS X process being swapped out, without code change?

I want hotkey-based utilities like Quicksilver or Zooom to respond immediately. But if they have been idle for a while, they (I guess) get swapped out, and respond slowly, sometimes not even ...
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Do locked pages get shredded from disk after resuming from suspend-to-disk?

Locked pages are sometimes used to store crypto keys like for Luks or for encfs and other sensitive things. But when doing hibernate (without swap drive encryption) they get stored to disk ...
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Disadvantages of using a swap file/partition on an SSD, even when swappiness is set to 0 [closed]

What are the disadvantages of using a swap file/partition on an SSD, even when swappiness is set to 0 I'm particularly interested in the /proc/sys/vm/swappiness=0 case. How much writes are still ...
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Linux: don't create swap partition?

I was wondering since I heard that swap is used when you're out or RAM and and swapping too much is bad, since I have a lot of RAM ( 8GB ).... what if I dont create a swap partition? Also, do I need ...
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868 views

Page Faults without Swap-File?

I've found the obvious question and also it's bigger brother over at ServerFault. But my question is quiet different: If Page Faults are the moments in which the OS needs to load something from the ...
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How to interpret Windows XP's Virtual Memory Info - the 10 numbers and 1 graph

How are the numbers in the Windows XP Virtual Memory info to be interpreted? I am actually just interested in: 1) What is the total size that is free as in "untouched" physical RAM, so that the ...
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Windows 8 pagefile on usb FLASH

Not duplicate :) Windows 8 hides usb flash drives in the list of virtual memory drive list. The picture taken when I installed 2 usb flash drives but they are not in the list. Any body knows the ...
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controling tmpfs memory usage

Any way to limit the amount of RAM used by tmpfs wihtout limiting the amount of swap? Most documentations says that tmpfs' size option will limit the total size of the tmpfs partition and later on ...
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'cache swap' filesystem for SSD/HDD combo?

As we all know, Solid State Drives (SSD) are expensive ($/Gb) but they are quick to access. I'm wondering if there exists a sort of software-kernel-level 'cache swap' filesystem technology; the idea ...
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Create Linux swap on external USB 3 hard drive

I have an external USB 3 hard drive USB 3 port on Debian, and I would like to create a swap partition on that drive which drive also holds the partitions for databases and other high-volume stuff. ...
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Unnecessary Swapping in Linux

It seems that sometimes, my computer will start swapping unnecessarily (memory usuage is ~25%), and I can't figure out why. It seems to happen most often when running Perl scripts, but these aren't ...
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how to configure Linux to call oom_kill on its own

I do not want my computer to swap data to disk. I have no swap partition: $ free total used free shared buffers cached Mem: 3841912 3670012 171900 ...
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478 views

Is there a way to exclude a specific drive vdi from “snapshots” in VirtualBox?

...or is there another space-efficient way of dealing with the page/swap file of the Guest O/S? I've realised that its quite possible/likely that one of the things which "bloats" the snapshot/diff ...
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How to load entire program from pagefile quickly?

Sometimes I do not use some programs with high memory usage (e.g. virtual machine with 2 GB of memory) for several days. When I return to it, its memory is mostly swapped onto HDD. When I try to work ...
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264 views

What happens when you try to hibernate but there is not enough swap available?

I have a Linux box with a swap partition of size RAM + x. Suppose more than x of the swap is already in use. Now I try to hibernate. Will the kernel randomly kill sleeping and/or not sleeping ...
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686 views

How do I prevent my computer from freezing when it starts to swap?

I work as a Java programmer, so I often have to run several programs at the same time that consume a lot of memory. When my memory is full and Linux starts swapping, my computer almost completely ...
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2k views

How to tell Linux to explicitly swap out main memory of a suspended process?

I run a memory-hungry process (mkcromfs) which consumes more memory than I have physical memory on my latop, so it is paging and swappin and thrashing all the time and loadavg is about 2 (compcache is ...
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swap rule 1.5 *memory= swap still valid [duplicate]

Possible Duplicate: Why should the size of the swap partition be double of the RAM size? Does the rule of 1.5 *memory= swap still apply in these days where systems can have32 GB of memory. ...
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Using SSD as Linux RAM

I have a very very fast SSD OCZ Revo. I want to use a lot of RAM but I'm limited to 4GB RAM for the moment. If I use my SSD OCZ Revo as swap (the whole of it, 160GB), does that mean I have effectively ...
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Force swapping of certain stopped processes

When I'm playing minecraft, my computer often has to swap because Google Chrome takes much RAM, too. So, I'd like to manually swap out Google Chrome. I know that I can temporarily stop all its ...
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319 views

Where is terminal scroll back information stored (how does tmpfs work)?

While trying to test something unconnected, I launched an infinite loop on my terminator terminal emulator which printed a lot of data to STDOUT. After running it for a few minutes, I noticed that my ...
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682 views

Does having swap space on a solid state drive affect the drive's lifetime?

Let's say you have an 8GB solid-state hard drive, which has a limited number of writes by nature (I think). If you have swap space for your Ubuntu installation, will the lifetime of your solid state ...
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More RAM than motherboard supports using ram disk + swap?

I want to put 6GB of RAM in a motherboard that supports 4. I heard something about using the excess RAM as a RAM disk and formatting that partition as SWAP, but that doesn't seen like it will work. I ...
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Any performance gain by putting Windows Pagefile.sys onto an Software RAID-0 Striped Volume?

I have a workstation class laptop running 64bit Windows-7 with 8GB-RAM (expandable to 16GB) and Dual SATA2 7200rpm disks. I know my system will be making heavy use of the pagefile since I will be ...
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disable pre-emptive swapping in windows xp

If I leave my XP pc for a while, it seems to swap most of my processes to disc. I come back to use it after X hours/days and each process takes 10-30s to get going as it loads it in off disc. It seems ...
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How to use compcache for Linux 3.2 (Debian Wheezy)

How do I set up and configure compcache for Debian Wheezy (3.2 kernel). As far as I can understand compcache is now in the kernel and is not to be found in the debian repo either. Compcache should be ...
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How permanently change Linux swap disk priority

I’m using two swap disks. Changing the order they are in in /etc/fstab and using pri in fstab doesn’t seem to have any effect. This is what it looks like in the /etc/fstab: #swap on other disk ...
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How to load entire process memory from swap quickly (linux)?

I run a bunch of CPU-hungry processes in parallel, they normally use a few GB of memory each. From time to time they allocate large amount of memory too (say 150-250GB). Usually at most one of the ...
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181 views

Pick which swap partition to use for Suspend to Disk

Is there anyway in Linux to pick which swap partition to use for Suspend to Disk? I have a setup with 2 swap partitions, one on an SSD and one on a HDD. I want the swap partition on the HDD to be used ...
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493 views

OS X “Swap used”

I'm a bit confused here, I'm trying to open a tab in Chrome and sometimes it takes few seconds while freezing my computer significantly so that I can't use even to bring Dock menu... I even closed ...
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Moving Swapfile in Mac OS X Lion

I had previously consulted this thread when using snow leopard to move all swap to an SSD: Moving the swapfiles to a dedicated partition in Snow Leopard The information appears to be out of date at ...
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Should I symlink my /private/var/vm dir to another volume in OS X Lion?

So I just installed an SSD in my MBP and have been a bit concerned about running out of disk space. I noticed that /private/var/vm holds an 8.6 gb sleepimage file as well as swap files. I'd be much ...
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Need more swap space - out of disk slots

A server I am using was setup incorrectly with only 1G of swap space. There are no more hard disk physical slots. There is content on the existing disks. I would like to resize the partition, but ...
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How can I make Windows XP use more than 2.5GB of RAM?

At work, I have four system with Windows XP SP 3 with 4GB RAM installed. When I start a lot of apps, I see that Windows gets unstable when more than 2.5GB of RAM is in use with the usual effects: ...
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How do I make two linux partitions share a swap partition?

I have two Ubuntu linux partitions, and each has its own swap space. Is it possible to make them use the same swap space?
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even if we have enough RAM space, why OS will use SWAP memory? [duplicate]

from the above pic, you can see we have 3191 RAM free, but at the same swap is also using about 661 bytes. why it is occurring ? can any give a glance regarding this. Thanks
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How to make a good guess for the swap partition size when using tmpfs?

I have an SSD, so space is a scarce resource. I'd like to use up as little as possible for swap. In fact, I have spent the last year completely without a swap partition (the computer has 6 GB RAM). ...
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Ubuntu memory usage

I'm running Ubuntu 10.04 and I do some dev with it. As I open FF, Chrome, Eclipse (Zend Studio 7.2), etc. and do some work, then leave, screen saver goes on, and when I come back a few hours later ...
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Sharing RAM resources between 2 or more computers

I know there was a somewhat similar question before: How to share CPU or RAM? But, let me just specify it a little more... When Microsoft Windows requires more RAM capacity than available it uses a ...
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What is the difference between swap entries in fstab?

I've been looking around and seen two different things ways to declare swap in fstab. I've seen something like the line below: UUID=UUID-HERE none swap sw 0 0 and UUID=UUID-HERE none swap swap 0 ...
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Too Much Swapping, even though RAM is ~75% Empty

I have a VPS with 9GB RAM, 300GB HDD, 3 GB Swap, 7 Cores. The OS is CentOS 5.7 Final. I have postgres9.0 running on my machine, with proper tuning done (at least by book/wiki of PostgreSQL). What ...
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swap file vs partition

I needed some more swap for something I'm doing so I set up a swap file rather than editing partitions. Are there any disadvantages to using a swap file instead of a swap partition? My OS is ...
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Can I use Nand flash as a swap memory in Embedded Linux?

I have 128 MB of Ram in one of my products, which was sufficient when we released first version of the product. But now we added some extra features in it, So this much Ram may cause a problem of OOM. ...
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What happens if you just unplug swap drive from running system?

I'm running heavily leaking apps on server which have already swapped out about 60gb of garbage in their over 100 days uptime. At the point when I've run out of swap for the first time (32gb) I ...
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how much swap space is too much on x64 and will cause problems?

Apart from using up too much disk space, how much swap space can you allocate before it will degrade performance or cause problems on an x64 OS? What differences are there between the x64 OSes? I'm ...
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Linux swap robustness and/or mirroring - kernel 3.2

i have 8x 2TB disks in raid6 with mdadm and I decided to add a little "slack" partition to each drive just in case a replacement drive is not exactly the same size of the drives i now use. The purpose ...
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Linux zram (compcache) + SwapCached

I have a question about zram + swapcached. I know that zram is a compressed swap in memory, but linux use it's own internal SwapCached area to store recent swap pages also in memory. I have a 512MB ...
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Temporarily adding my user to another system

So i need to send in my mac laptop for repair and i have plenty of development work to do for the week that it will be gone for. I can borrow a laptop but obviously it wont have my data and dev stuff ...
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1answer
113 views

Windows obstinately shrinking the pagefile

I admit I have rather small free space available on my C:\ drive (only 3-4 GiBs usually, with a 4 GiB pagefile being around), but what really annoys me is this: Windows sometimes does an operation(1) ...
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Why does swapon take ages when enabeling a swap file?

I've created a swap file with dd if=/dev/zero of=swap.img bs=1024k count=4k mkswap swap.img swapon swap.img While this works, the swapon command takes ages (approx 10min) to finish. Enabling the ...