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I used btrfs defrag and compress (zstd) on my video server qcow2 image. It freed up 153GBs

Not really sure how or why, but the filesystem was saying that 799GBs of space were used when only about 650GBs were actually being used, probably had something to do with btrfs :cirno_shrug:

before:
filefrag base.qcow2
base.qcow2: 84874 extents found

after:
filefrag base.qcow2
base.qcow2: 26533 extents found

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@SplitShockVirus Is the number of files and sum of the actual filesizes still the same? ;) Or did it just "lose" some

@sjb That's actually a valid question, and one that I don't know the answer to. I just run commands, expecting them to "just work" and deal with the consequences after.

Let me md5sum it and compare with my freenas backup.

@SplitShockVirus It's probably just defragged. I like the fact NTFS tells me both "size" and "size on disk" for this sort of situation

@sjb The file sizes are technically different on two different filesystems (zfs with lz4 and btrfa with zstd). Still waiting on the md5sum. The underlying filesystem in the qcow2 image should not have been touched nor would any of the data, just the image compressed.

@sjb Like magic 😎 ☕

~/media/volgroup2-data/.local/share/libvirt/images/mercuryv3]$ md5sum base.qcow2
2fb03abd41a7614c6cf0ddbb39100386 base.qcow2

~/media/nfs/Archive/Backups/libvirt/images/mercuryv3]$ md5sum base.qcow2
2fb03abd41a7614c6cf0ddbb39100386 base.qcow2

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A mastodon instance created by Derek Taylor, creator of the DistroTube channels on YouTube and LBRY. Derek is an advocate for free and open source software.