Questions tagged [sparsefile]
The sparsefile tag has no usage guidance.
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Is there a tool like `dd` but respect sparse-ness of input file?
I am creating disk images with multiple ext4 partitions on it. Each ext4 partition content is created with mkfs.ext4 and the resulting filesystem image files are "sparse".
When I use dd to ...
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dphys-swapfile on btrfs volume fails
I have used dphys-swapfile with the default path of /var/swap and a 2048M swap file.
However, since /var/swap is on a SD card, I wanted to move the swap file to a magnetic disk. So I ran sudo dphys-...
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How can I remove holes in a sparse file on Linux?
How do I remove all holes in a sparse file on Linux? On Windows, I believe the procedure is
fsutil sparse setflag <file> 0
What is the Linux equivalent?
(I know cp <file> <file>.cp; ...
- 1,735
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How to shrink sparse files in same way as rsync does in linux after copied them without "-S" operator?
I try to take a backup of a disk.
I use rsync to backup files between disks.
However, while used --delete option in rsync alone and then backup, destination disk is almost full while source not.
By ...
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Is there a Windows equivalent to fallocate --punch-holes?
I'm looking for a way to punch holes in files on Windows such that the actual size-on-disk goes down, and the area that is punched gets deleted. Identical to the behavior of fallocate --punch-holes on ...
- 299
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How does my spinning HDD reach 320 MB/s?
While creating an image of a (mostly empty) 1TB spinning hard disk, I was expecting a read speed of around 120 MB/s, and on the first blocks it was like that, but after that, most of the time it was ...
- 1,704
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How to re-sync already transfered sparse file with rsync?
I have completely transferred a file using rsync without the use of the --sparse, -S option. I don't want to waste space and thus re-sync the file and turn it into a sparse file. Is there a way to ...
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Can I somehow split one single file between drives? Windows
I want to split a bigger file (virtual machine disk) between my available drives.
Is it possible? If so, how would one do it?
Simple use case: In today's world, you may have many different drives in ...
- 16.2k
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Why can't I create sparse files on my NTFS partition under Linux?
I have a very large sparse file on an EXT4 partition, and I want to copy that file to an NTFS partition. The file has a size of about 2 TB, but since it is a sparse file it uses only 700 GB on disk.
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How to compare huge sparse files efficiently?
There are two sparse files. They are proved identical by diff. But it took 20 minutes (too long time) to compare. I am thinking of taring them into tiny files to speed up the comparison. But they tar ...
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How can I create a scenario to test zerofree?
What I am doing
I am studying the filesystem image sparse tool: zerofree.
I imagine the steps to create the scenario should be that:
create a file system image.
use some way to fill it.
clear it, but ...
- 21
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Is it safe to interrupt when "fallocate --dig-holes" is running?
I use fallocate --dig-holes on very large disk images to make it sparse in-place. I'm worried that this operation may not be atomic. My questions are,
Is my data guaranteed to be safe (holes are ...
- 123
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File NOT set as sparse but sparse attribute is seen set on windows explorer
There is a test file in windows machine where it is seen having sparse file attribute (P). But suing fsutil sparse queryflag says the file is not sparse. Even queryrange range says the same.
This is ...
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Determining status of cloned file on APFS
Apple is now using APFS across several product lines, including macOS. This new filesystem has some nice features for minimizing how much actual disk space is consumed, such as sparse file support ...
- 318
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Compact transfer of partially empty blockdevice images for further compression
I like to do backups from a bunch of linux block devices on remote machines. Currently I am transferring the complete block device, albeit almost empty, to the backup machine and compress or ...
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