Using swap files to expand swap space on Linux

Imagine a scenario where our Linux system runs out of swap space, in which case we want to expand the swap space with the swap partition, but in some cases there is no free partition available on the disk, so we can't expand it.

Therefore, in this case, we can use the swap file to increase the swap space.

Here are the steps:

1. Check the size of the existing swap partition

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We can see that the size of our existing swap partition is 2G, and now we extend it to 1G.

2. Create a 1G size normal file 650) this.width=650; "Src=" http://s4.51cto.com/wyfs02/M01/77/C0/ Wkiol1ztcgaazyz0aaa9wflgtfa242.png "title=" DD. PNG "alt=" Wkiol1ztcgaazyz0aaa9wflgtfa242.png "/>

We used the DD command to create a swapfile file.

If indicates from which location to read

of where to export

BS indicates how large one reads

Count indicates how many times read writes

3. Set the swap file permission to 600 to prevent ordinary users from deleting this file.

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4. Format Swap

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5. Turn on swap

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6. Set up a new swap file to boot

Edit File/etc/fstab

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Specifically because my swapfile file is under Root's home directory, so I added a line

/root/swapfile swap swap defaults 0 0

5. Check the size of the swap partition again

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Complete the extension!

This article is from the "focus on Java,linux Technology" blog, please be sure to keep this source http://wuqinglong.blog.51cto.com/9087037/1722583

Using swap files to expand swap space on Linux