Add zram-to-zswap migration script - #15
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Audits a host's current zram/swap setup and migrates it to zswap (compressed cache in front of real disk swap) instead of zram-only swap, per https://chrisdown.name/2026/03/24/zswap-vs-zram-when-to-use-what.html. Supports dry-run, ZFS/LVM/swapfile auto-provisioning, dynamic sizing based on host RAM, and backup/revert of everything it touches.
Live-tested --apply/--revert on a real VM: when zram-config's postinst had already auto-started the service with the stock init script, 'systemctl enable --now' on the already-active oneshot unit was a no-op, so our restored custom script never actually ran. Now stop the service and reset any zram devices apt created before restoring the custom script and restarting.
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Summary
Bash/Server scripts/zram-to-zswap.sh, a script to audit a host's current zram/swap setup and migrate it to zswap (compressed cache in front of real disk swap) instead of zram-only swap.Features
--applyto actually change anything)/etc/fstab, the kernel cmdline file, and the originalinit-zram-swappingscript before making changes, with a--revert [--apply]mode to undoTest plan
bash -nsyntax check passes--applyrun end-to-end on a real Ubuntu 24.04 VM (zram-only → swapfile + zswap); confirmed viaswapon, GRUB cmdline, and/sys/module/zswap/parameters/*--revert --applyrun on the same VM; found and fixed a real bug wheresystemctl enable --nowdidn't restart an already-active zram-config service, so the restored custom init script never re-ran. Fixed by explicitly stopping the service and resetting zram devices before restoring the script and restarting. Re-tested after the fix — confirmed clean.--applyafter revert to confirm idempotency (reused the existing swapfile rather than recreating it)