[Verizon LG G2] MidnightHarvester:
INTERESTED IN A BETTER LAGFIX?

Here is a small script which goes a little further than the Lagfix app in the PlayStore. This was originally posted in a different thread dedicated to a ROM so I'm trying to clean this post up as much as possible.

Caution!

A quick word of warning. Take the same safety precautions with this as you would the LagFix app. Both use the same utility which has been found to brick some devices. This was originally written for the VS980 (LG G2) and for a 4.2.2 ROM (fstrim support is native in 4.3+) though it should work fine as long as your device is compatible with the LagFix app (although you may need to tweak a few things)

Prerequisites

To begin with, you'll need a fstrim binary located in one of your device's PATH directories. A safe bet would be to drop it in /system/bin/ or /system/xbin/. Don't forget to change the permissions as well so it can run. If in doubt it's safe to give it full read/write/execute (I vouch for the one I link to at least...)

If you'd like the script to run on boot, then having init.d support on your ROM is ideal. If you don't have native init.d support, search xda as I've seen a "How to Enable init.d on Any Device Even Stock" how to floating around somewhere.

Finally, you'll need the filesystems-fstrim script that's also linked to at the end. The script basically performs three actions. First, it remounts all the filesystems (see note at the end if not on a LG G2) without the 'discard' flag. Since we will be running the fstrim utility on boot (or manually of you desire), having the OS clean up after deleted/moved files on the fly isn't necessary at all and just slows performance down noticeable. After that it attempts to trim each mounted volume oo your device (think defragment), then finally it writes all output to /$ANDROID_USER/logs/ (bytes trimmed from each mount, etc).

This script will trim other mounts besides /system, /cache, and /data. That and the fact that it removes the 'discard' flag is why I wrote it for personal use instead of using the app in the PlayStore (also nice having a record I'm /data/logs as well).

How to Run At Boot

With the fstrim utility in .../bin or .../xbin (with proper permission, and init.d support on your ROM and the 03-filesystems-fstrim script you're ready to go. Drop the 03-filesystems-fstrim script into your init.d directory and set permissions (it's safe to give it full read/write/execute access if unsure) and you're ready to go. Your init.d directory may vary depending on ROM. I'm used to always using /system/etc/init.d, but some ROMS (CyanogenMod for example) uses a different path. Ensure that it runs after any other scripts you may have in init.d which remount the filesystems to ensure that the filesystems aren't remounted elsewhere with the 'discard' flag. You can do this by appending a number to the beginning of the filename that's higher then the others (for example you could rename it 99-filesystem-fstrim and it will run after 01tweaks or whatever might be there already). More information on init.d can be found with a Google search as it's covered everywhere.

Now, at this point on next boot the script should run and if there are logs in /data/logs/ you can read them to determine if it succeeded or not. If successful, you won't see any error messages and on the mounts that were trimmed it will let you know how many bytes off each.

Notes

I wasn't expecting this post to get moved into its own thread and was sharing this to oothers using the same ROM I was. The section of code that remounts all the filesystems is hardcoded, so that section may fail on other devices that have a different structure {and having a filesystem mounted with 'discard' flag kind of defeats the purpose of trimming to begin with ;) ), so you may need to change this section. If editing, use a text editor that allows you to turn word wrap off as for one, it can create nasty messes in the code with strange like breaks/etc and two, it's good habit anyways when dealing with any script or programming language. I used 920 Text Editor which is pretty decent but there are plenty other good ones in the Play Store. Running the 'mount' command with no arguments after it at the command prompt can help you map the filesystem on your device with the corresponding LG G2 one.

Files are currently hosted on my Drive until I find another browser that works or get on a PC. If you already have the fstrim binary you don't need this one..Feel free to PM Amy questions or ask here.

download ~ fstrim binary (rename to 'fstrim' without any extension

download ~ filesystems-fstrim script (again, strip off any extensions in the file name