[Nexus 7 (2013) Original Android Development] jubei_mitsuyoshi:
This is the flo version of my mod for the old nexus 7 here http://xdaforums.com/show....php?t=2280496

Repeating the intro to save you guys going there

Background..

With any linux system i build first thing i do is remove the journal from all my EXT4 partitions, to make a long story short ( i wont bore you with details of just how journal writes totally slow disk i/o , google it ) this gave me on average a 25% increase in system speed ( obviously due to the increased i/o rate )

I usually did it with

mke2fs.ext4 -O ^has_journal ...device...

before installing the distro, now i thought hey maybe this would work on android?

Now mke2fs is not well supported on arm but tune2fs is! in fact its included in TWRP 2.5 so

run_program("/sbin/tune2fs", "-O", "^has_journal", "/dev/block/platform/msm_sdcc.1/by-name/system");

( for the system partition) should work right , and in fact yes it does !!!, tried it from TWRP command line and hey presto %^$%^$^%$ FAST system

This is the code for a recovery script version

ui_print("jubei.....remove journals from all ext4 partitions");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/boot /boot emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/recovery /recovery emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/misc /misc emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/system /system ext4");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/userdata /data ext4");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/cache /cache ext4");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/sbl1 /sbl1 emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/sbl2 /sbl2 emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/sbl3 /sbl3 emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/tz /tz emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/rpm /rpm emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/aboot /aboot emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/sbl2b /sbl2b emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/sbl3b /sbl3b emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/tzb /tzb emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/rpmb /rpmb emmc");
ui_print("/dev/block/platform/msm_sdcc.1/by-name/abootb /abootb emmc");
ui_print("");
ui_print("");
ifelse(is_mounted("/system") == "/system", unmount("/system"));
ifelse(is_mounted("/cache") == "/cache", unmount("/cache"));
ifelse(is_mounted("/data") == "/data", unmount("/data"));
ui_print("converting partitions to ext4 minus journal");
ui_print(" ");
ui_print("e2fsck system partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/system");
ui_print("e2fsck data partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/userdata");
ui_print("e2fsck cache partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/cache");
ui_print("now lets rub out those nasty journals");
ui_print(" ");
run_program("/sbin/tune2fs", "-O", "^has_journal", "/dev/block/platform/msm_sdcc.1/by-name/userdata");
run_program("/sbin/tune2fs", "-O", "^has_journal", "/dev/block/platform/msm_sdcc.1/by-name/system");
run_program("/sbin/tune2fs", "-O", "^has_journal", "/dev/block/platform/msm_sdcc.1/by-name/cache");
ui_print("and re-fsck to clean any set bits");
ui_print(" ");
ui_print("e2fsck system partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/system");
ui_print("e2fsck cache partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/userdata");
ui_print("e2fsck cache partition");
ui_print(" ");
run_program("/sbin/e2fsck", "-p", "/dev/block/platform/msm_sdcc.1/by-name/cache");
ui_print("end of jubei mod ");

And i include a zip for those who like to test

there are 2 scripts, one to remove the journal from your ext4 partitions, and one to re-instate the journal, this should allow people to test their setup with each without any wiping or reformatting

Instructions.......

( tested with TWRP 2.5+ only )

Flash the bugger

DO NOT WIPE ANYTHING, after flashing, doing so will only reformat the wiped partition with a journal

There will be one update that includes a test routine to ensure journals have been erased

I am now able to extend the mod to any device that uses twrp 2.5+ and ext4, plese ask for a particular device on this thread

Thank you

Edit Please note non flo versions are not tested by me.

Edit mako version added after request

Edit hammerhead version added after request