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README.md

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 # portage-squashfs
 
-scripts to use squashfs to dramatically reduce the size of /var/db/repos/gentoo (or /usr/portage)
+scripts to use squashfs to dramatically reduce the size of `/var/db/repos/gentoo` (or `/usr/portage` if you're old)
+
+## Should I do this?
+Probably not. Chances are if you're running Gentoo you've never noticed how much space `/var/db/repos/gentoo` takes up. You would only care if you're running Gentoo on ARM chinky boards with low storage / write speeds. Or if you're me, running it on a chromebook with like 16Gb of storage...
+
+## MASTER / SLAVE structure:
+My trick here is to use a MASTER computer (like a server you run 24/7 or a beefy desktop) that also runs Gentoo. The MASTER compresses its copy of the Gentoo repo into a file using squashfs. The SLAVE downloads this copy into a folder and mounts it at `/var/db/repos/gentoo`. The files are still there as far as the SLAVE's portage cares, so you can proceed to install packages as normal. **Also both master and slave need the** `sys-fs/squashfs-tools` **package!!**
+
+In short:
+
+### MASTER
+- takes care of gentoo repo updating
+- squashes its copy of the gentoo repo into squashfs file
+
+### SLAVE
+- NEVER updates normally
+- only downloads squashfs from MASTER
+- mounts said squashfs
+
+## scripts
+- `portage-squashfs.sh` should be at the MASTER computer
+    - I put this one under `/etc/cron.daily/` as I already have a daily `emerge --sync` script in there.
+- `update.sh` should be at the SLAVE computer
+    - This one was made to be run deliberately instead of automated.
+
+## FURTHER READING
+- https://wiki.gentoo.org/wiki/SquashFS
+- https://forums.gentoo.org/viewtopic-t-465367-start-67-postdays-0-postorder-asc-highlight-.html
+- https://www.brunsware.de/blog/portage-tree-squashfs-overlayfs
+
+### FEEL FREE TO DO WHATEVER YOU WANT WITH THESE SCRIPTS, MODIFY AS YOU WISH