Questions tagged [swap]
Unix systems, and other Unix-like operating systems, use the term "swap" to describe both the act of moving memory pages between RAM and disk, and the region of a disk the pages are stored on. In some of those systems, it is common to use a separate whole partition of a hard disk for swapping. These partitions are called swap partitions.
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How do I add swap after system installation?
I did not create a swap partition during Ubuntu installation. Later, I freed up some space and made a swap partition. Now after each boot up, I am manually opening gparted to right-click the swap ...
user13593
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How do I configure swappiness?
I need a step-by-step, simple and easy way to configure swappiness.
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How to increase swap space?
I have, by default, 250MB of swap space in Ubuntu, and I want to expand it to a larger size. I need 800MB, which I think will be enough to open several applications without having to hit the current ...
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I have 16GB RAM. Do I need 32GB swap?
I read many places that the rule of thumb for swap space is to double the amount of physical RAM. However, 32 GB does seem a LOT. Do I need that much? Do I need it at all with this high amount of ...
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How much swap should I take for 1GB to 8TB of RAM on 14.04 or higher?
I'm going to install 64 bit 14.04 on a new machine with something like 1 to maybe 128GB RAM and even more RAM later. How much space should I allocate to the swap partition?
And especially: WHY those ...
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Hibernate and resume from a swap file
I have configured a new Ubuntu installation in a Notebook to use a swap file, instead of using a swap partition.
By default is not possible to get Ubuntu to hibernate using a swap file, so I tried ...
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How do I increase the size of swapfile without removing it in the terminal?
Is there a way to increase my existing "swapfile" without having to destroy and re-create it?
I would like to up my swap space from 1GB to 2GB. Currently it is set up as such:
$ sudo swapon -s
...
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What to do about "the disk drive for /dev/mapper/cryptswap1 is not ready yet or not present"?
While booting Ubuntu 12.04, the disk drive for /dev/mapper/cryptswap1 is not ready yet or not present is showing. Why is this?
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Adding a new swap file. How to edit fstab to enable swap after reboot?
I've deleted my existing swap partition due to some partitioning problem. I don't have a swap space now so I've created a swap file with:
dd if=/dev/zero of=/root/myswapfile bs=1M count=1024
Here's ...
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swap partition vs swap file
I was reading the new changes with Ubuntu 17.04 and one caught my eye which was moving from the typical swap partition model to a new swap file model for new installs.
Are there benefits for using ...
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Why are swap partitions discouraged on SSD drives, are they harmful?
I often read that one should not place swap partitions on a SSD drive, as this may harm the device. Is this true? Can you please explain the reason to me?
Because I otherwise would have thought that ...
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Why most people recommend to reduce swappiness to 10-20?
I have seen in several site which recommend to reduce swappiness to 10-20 for better performance.
http://community.linuxmint.com/tutorial/view/998
https://sites.google.com/site/easylinuxtipsproject/...
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Why is swap being used even though I have plenty of free RAM?
I thought the whole essence of swap was to act as a temporary storage safety net when RAM was full but my swap partition is constantly being used even though I sometimes have as much as 3GB free RAM. ...
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How do I increase swapfile in Ubuntu 18.04? [duplicate]
I have laptop with 8 GB RAM and 1TB HDD. I have swapfile which is 2 GB (Ubuntu 18.04 uses a swapfile instead of a separate swap partition by default) and I want to increase it to use hibernation.
I ...
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How do I resize partitions using command line without using a GUI on a server?
I only have access to the server via a terminal and I can't use graphical tools such as GParted!
I want to create a new partition from a part of the root (about 768mb) for swap.
# df -h
Filesystem ...
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Ubuntu 18.04 error on waking up from sleep : Read-error on swap device
After the laptop has been in sleep mode for a couple of hours,when I try and resume my session I get the following error:
Read-error on swap device
It takes about 30 seconds for the login screen ...
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How do I disable swap?
I have some sensitive data in RAM that I prefer not to be on disk. How do I disable swap?
I have more than enough RAM. If RAM consumption gets too high I have no problems with processes being ...
user4482
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Do we still need swap partitions on desktops?
I have read this question, but it was asked in the context of servers not desktops or notebooks.
If a good amount of RAM is installed on a notebook, say 8 GB, do we still need a swap space?
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Slow boot - "a start job is running for dev-disk-by..."
I don't recall when the issue started to occur but it's likely when I moved my VMWare Ubuntu image to an external SSD so that I can use the OS on any of my PCs. There aren't many links on Google about ...
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How do I setup an encrypted swap file?
When I installed Ubuntu, I setup an encrypted home partition. Now I have come to an issue where I am running out of memory because I haven't setup swap. How can I setup an encrypted swap file?
A ...
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What is a "Swap Area"?
So I noticed this question has not been asked directly;
What is this "Swap Area" people keep referring to when it comes to installing Ubuntu?
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kswapd0 is taking a lot of cpu
kswapd0 is taking 99.9% of my CPU as top shows me, the problem appeared today when gaming and first time it went away after 6 minutes and now it has been doing it for about 20 minutes. How is this ...
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Importance of Swap Partition
What is the purpose of a swap partition?
How do I know I have just enough swap partition? Not too much/little.
My Ubuntu PC is used for typical stuff:
Web (email, facebook, etc.)
Some movies
gaming ...
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Swap not working on clean 14.04 install using encrypted home
Update 3:
I decided to reinstall the system from scratch to remove any old cruft lying around since I had been experiencing some other issues after the upgrade aswell. Howver, this issue persisted.
...
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What is swap and how large a swap partition should I create? [duplicate]
I have a system with 4gb of RAM and Intel i5 processor. I want to know how much memory I should allocate to SWAP. Will allocating more memory help increase the system performance.
In the past i have ...
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How to recover data from NTFS partition that was made into a Swap partition?
I have extremely important stuff on my windows partition which during the ubuntu 10.10 installation,when it said that I should create something called swap space, I selected it to be a swap space (...
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Swap partition to Swap file [duplicate]
I'm having Swap partition of 8 GB , how can i create a swap file from it ? Currently having three partitions root , home , swap . So if i create a swap file how do i create it and where do it get ...
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How can I turn off swap permanently?
Swap makes my system all sluggish and turning it off makes everything smoother. I have 3.5 GB of RAM.
I know how to turn swap off by entering sudo swapoff -a in the terminal, but that's just for the ...
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Check if partition is encrypted
How do I check if a partition is encrypted? In particular I would like to know how I check if /home and swap is encrypted.
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How to empty swap if there is free RAM?
When I open a RAM-intensive app (VirtualBox set at 2GB of RAM), some swap space is generally used, depending on what else I have open at the time.
However, when I quit that last application, the 2GB ...
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Is it safe to turn swap off permanently?
My system was getting slower, especially when I use browsers like Firefox / Chromium and Virtual Machines. I noticed that I've got at least 3.2 GB of free RAM (using Gnome system monitor) and there ...
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Default 17.04 swap file location
I could not find any information on this anywhere (and I don't want to set up a new 17.04 installation just for that), what is the default location of the swap file in 17.04?
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Encrypted Swap Partition for 14.04
How can I produce an encrypted Swap Partition for 14.04 ?
All the advices I saw here are for versions <14.04 and do not work for me.
I tried a lot but nothing lasted longer than a reboot.
On ...
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Increase size of encrypted swap
Ubuntu 18.04 is by default creating a random encrypted swap during each boot using dm-crypt/Swap encryption. For me, this is creating a 1gb swap but I cannot find where to increase the size of the ...
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No swapping on LUbuntu at enabled swap
I have tablet with 4 GiB of RAM and SSD 128 GiB with LUbuntu 18.04.
When the memory usage reaches approx. 3.9 G, the system hangs. Only the mouse pointer moves with lags. No reaction on Ctrl+Alt+Fx.
...
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Increase Swap in Ubuntu 18.04 Under Lvm and Encrypted File System
I did a clean install of Ubuntu 18.04 Desktop.
I used the graphical installer and chose "Encrypt the new Ubuntu installation for security".
It used by default LVM and created a partition for the ...
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Increase swap in 20.04
I'm running Ubuntu 20.04, and I'm trying to create a hibernate command. I'm following these instructions.
Step 2 says
Then check whether the swap memory you allocated is more than or at least equal ...
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Does it make sense to create swap partitions for new installations nowadways?
For a desktop installation in a new and shiny laptop (let's say 16gb ram and ssd hd), does it make sense to have a swap partition?
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How to decide on Swap size [duplicate]
I wanted to just confirm how much the size of Swap partition should be. Lots of places tell that the swap size should be twice the size of RAM. Somebody also told me that it shouldn't be more than 8 ...
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Is it still bad to use swap on a modern SSD?
I have a Samsung 960 Pro SSD with Ubuntu 18.04
is it safe to put the swap file on there or would it hurt it in the long run,
I heard some people saying that new SSDs don't suffer from that issue ...
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Unsafe swap space detected
So I had a Ubuntu 13.04 installation and I had encrypted my hard drive while I was doing installation. I was playing around and mistakenly deleted all the partitions, now I downloaded lUbuntu 13.10 ...
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Do I need a swap partition? [duplicate]
I have 4GB of RAM and I want to install Ubuntu. Do I need a to have a swap partition? Because my computer has 4GB RAM, I do not think it is necessary to have a swap partition. If I do need to have a ...
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How to disable cryptswap?
How can I disable cryptswap? I would like an unencrypted swap like before.
This is on an ubuntu 9.10 system.
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How do I restore a swap partition I accidentally deleted?
I accidentally deleted my swap partition via gparted.
(I'm still logged in the system so restoring should be easier) Can someone help me please? I'm not sure how to configure it because the Ubuntu ...
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Sharing of swap partiton between linux systems?
I have a laptop on which I have installed Ubuntu 12.04 and Windows
Now just for learning purposes I am going to install Backtrack OS on it.
My laptop has 4 GB of RAM so according to the ...
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How to permanently enable compressed ram swap? What version to use?
EDIT: In precise there's now zram-config. It's an upstart job compressing up to half of your ram spread over $(number of CPU cores) swap devices. It didn't allways start at boot but issuing sudo ...
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How can i increase size of swap file? [duplicate]
I'm new to Ubuntu . I need to increase size of swap file from 8 GB to 16 GB , how can i do it ? and is that in this file /etc/fstab ?
by command free -h
total used free ...
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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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How do I find out if I have a swap partition on my hard drive?
I used the 12.04 live cd to install Ubuntu over my Windows 7 partition and deleted everything so I just have Ubuntu on my laptop. But since during the installer I chose the simple "erase entire disk" ...
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fallocate vs dd for swapfile?
I'm wondering what the difference is between creating a swapfile with
fallocate -l 1G /swapfile
and
dd if=/dev/zero of=/swapfile bs=1024 count=1024
both seem to work fine, but does one have an ...
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