*CHECKPOINTCTL-DIFF*(1)

✨ checkpointctl-diff — the glow-up your checkpoints deserve 💅

okay bestie, so this is checkpointctl-diff(1) from the CHECKPOINTCTL manual, and it's literally here to spill the tea on what changed between two container checkpoints. no cap, it's iconic. 🌸

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🦋 SYNOPSIS

checkpointctl diff [OPTION]... CHECKPOINT_A CHECKPOINT_B

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💖 DESCRIPTION

You hand it two container checkpoints and it compares them, showing you the diff in:

• Process tree — new, removed and modified processes 👀
• File descriptors — files that got opened or closed 📂
• Sockets — network sockets that appeared or vanished 🔌
• Stored memory page-image sizes — the sizes as they're stored on disk 🧠

Command lines and environment variables? Those get read straight from the memory pages inside each archive. CRIU LZ4-compressed pages are decoded automatically — and heads up, that needs checkpoint/inventory.img. ✨

lowkey important: compression can change the stored page-image sizes without changing the process memory at all. the size_change_mb field in the JSON output is measured in MiB, fr fr.

Each checkpoint's details show CRIU compression: Enabled or CRIU compression: Disabled. The JSON output includes the boolean field criu_compression in both checkpoint_a and checkpoint_b. This setting is about CRIU memory page compression — independent of archive compression, don't get it twisted. And archives that don't have checkpoint/inventory.img? Those get reported as compression disabled, for compatibility with older checkpoints. slay 🫶

Container created shows when the container was created, so it's the same for checkpoints of the same container (obviously, bestie, it's the same container 😭). The JSON output keeps this timestamp in the created field of checkpoint_a and checkpoint_b.

Checkpoint data size is the combined size of the files under checkpoint/, memory images and CRIU metadata included. It reflects CRIU page compression but not compression of the archive. The JSON output keeps this value in total_size. the way that's so specific and yet so necessary 💜

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🎀 OPTIONS 🎀

• -h, --help — show help for checkpointctl diff. ask and you shall receive, bestie ✨
• --files — include file descriptors in the diff 📂
• --format=FORMAT — specify the output format: tree or json (default "tree") 🌈
• --ps-tree-cmd — include full command lines in the process tree diff
• --ps-tree-env — include environment variables in the process tree diff 🌱
• --show-unchanged — show entries that are identical between the two checkpoints (yes, the boring ones too, we're being thorough)
• --sockets — include sockets in the diff 🔌

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🌟 EXAMPLES

Compare two checkpoints with the default tree view:

$ checkpointctl diff checkpoint1.tar checkpoint2.tar

Show differences including file descriptors and sockets:

$ checkpointctl diff --files --sockets checkpoint1.tar checkpoint2.tar

Include command line arguments and unchanged entries:

$ checkpointctl diff --show-unchanged --ps-tree-cmd checkpoint1.tar checkpoint2.tar

Output differences in JSON format:

$ checkpointctl diff --format json checkpoint1.tar checkpoint2.tar

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👑 SEE ALSO

checkpointctl(1) — go read the main character's page too, iykyk

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💜 AUTHOR

The CRIU team 🫶

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and that's the whole vibe check, bestie — this page is from the checkpointctl manual, dated 2026-10-19. go diff some checkpoints, you ate 💅✨🎀