fallocate linux command


You all are familiar with the dd command. I know that the same dd command that we have used extensively during our Red Hat Training under RHCE or RHCSS curriculum. And if you remember we had used it for created swap files etc.

Fine with dd, till now.

NOW lets welcome – fallocate.

Its is a very neat command that can save you a lot of time.

dd command is normally limited by the device speed, which is about 80MB/s for most disks. fallocate solves the problem by preallocating blocks instantly.

Its indeed a new command and is introduced in Linux kernel 2.6.23.

Now, fallocate will remain this fast, without any regard to file size, while dd times will increase.

So GEEKS, when you have to create files that are several GB is size or much larger, you will LOVE fallocate.

Here is a illustrated example, showing the enormous speed of fallocate.

fallocate linux command

fallocate linux command