Use this tag for the fallocate command, NOT fallocate system call.
Questions tagged [fallocate-command]
7 questions
11
votes
1 answer
What are the holes in files created with fallocate?
If we create a swapfile with fallocate we are told that the file contains holes and therefore the operation is halted.
What are these holes?
Is it unallocated disk space, which makes the whole file allocation a hole itself?
Like this:
block1 ->…
Nelssen
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10
votes
2 answers
What is the difference between `fallocate --dig-holes` and `fallocate --punch-hole` in Linux?
I totally understand that --dig-holes creates a sparse file in-place. That is, if the file has holes --dig-holes options removes those holes:
Let's take it in a very simplified way, let's say we have a huge file named non-sparse:…
direprobs
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4
votes
2 answers
Can losetup be made efficient with sparse files?
So my setup is like this.
$ truncate -s 1T volume
$ losetup -f --show volume
/dev/loop0
$ mkfs.ext4 /dev/loop0
$ ls -sh volume
1.1G volume
$ mount /dev/loop0 /mnt/loop
Now I have a 1.1TB volume, as expected. The overhead of ext4 expanded the sparse…
Daffy
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1
vote
2 answers
What kind of content/data does "fallocate" command generate?
When is executed the sudo fallocate -l 2G /swapfile command, then 2 GB is created, but with that kind of content or data? Can be it customized? If yes How?. I did do some research but there are no details about this. I want to know if is good use…
Manuel Jordan
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1 answer
Is it possible to zero the free space on a LUKS volume?
I want to have a LUKS volume as a loopback device pointing at a sparse file. Lets say I put a 20gb file on it, then later I delete it. How can I zero that area on the device itself so I can fallocate -d the loopback file to reclaim the space?
Daffy
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0
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0 answers
Can't resize mounted file to dir after increasing size (fallocate)
I created a file to mount as /tmp dir to limit it's size so it cant crash the system. I used mkfs.ext4 on it and it mounts in /etc/fstab. Now I need to increase the size, so I used fallocate again, and the /tmpfile shows larger now, but when mounted…
alchemy
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0
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1 answer
Why dd speed decrease significantly after fallocate once
Why fallocate -c -l1GiB once cause the second loop of dd speed decrease from 1.0 GB to ~200 MB/s ?
xb@dnxb:~/Downloads/test$ fallocate -l 10.2GiB lala.mp4
xb@dnxb:~/Downloads/test$ ls -larthiF --context --color
total 11G
41680908 drwxr-xr-x 121…
林果皞
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