Need someone with the Android 7 update and can run terminal commands

[Jerry Hildenbrand]

Ideally, someone who has reformatted with f2fs, too.

Looking to see if the nobarrier disk mount option is being used. You can check by running mount with no parameters from a terminal.

Why I even care (all kinds of nerd below this line)

when you mount a disk (primary or logical) with the nobarrier option, you've made fsync() a no-op.

The fsync() function forces data in the buffer to be actually written to the disk when called.

A no-op means that the command is interpreted as being blank and skipped.

Mounting a disk with nobarrier means that you're not forcing the buffer to be written and is a good way to lose data. It's from "trust the file system and someone else to take care of it" school of thought. Because you're not forcing data to be written, disk access times are much faster (on paper, we're talking about nanoseconds here) than when fsync() is called.

Lenovo is using this hack on the Moto Z. Curious if OnePlus is doing it, too.

 

[fuzzylumpkin]

What up Jerry.

I formatted my Oneplus 3 to f2fs today, and with the caveats that I used TWRP so this may not be relevant and that my Linux game isn't as sharp as it could be, it seems that my storage is NOT mounted with nobarrier enabled... It was also disabled when it was formatted in ext4, not that you'd expect different.

Here's the string from terminal emulator i believe you're interested in:

dev/block/dm-0 on /data type f2fs (rw,seclabel,nosuid,nodev,noatime,nodiratime,background_gc=on,discard,user_xattr,acl,inline_data,inline_dentry,flush_merge,extent_cache,mode=adaptive,active_logs=6)

And here's a full terminal output dump in case I'm wrong:

So, code tags are banned here, eh? At least I had the sense to copy my post... The second time lol. A warning message would've been nice :/ this is gonna be long...

OnePlus3:/ $ mount
rootfs on / type rootfs (ro,seclabel,size=2843548k,nr_inodes=710887)
tmpfs on /dev type tmpfs (rw,seclabel,nosuid,relatime,size=2920852k,nr_inodes=730213,mode=755)
devpts on /dev/pts type devpts (rw,seclabel,relatime,mode=600)
none on /dev/cpuctl type cgroup (rw,relatime,cpu)
adb on /dev/usb-ffs/adb type functionfs (rw,relatime)
proc on /proc type proc (rw,relatime,gid=3009,hidepid=2)
sysfs on /sys type sysfs (rw,seclabel,relatime)
selinuxfs on /sys/fs/selinux type selinuxfs (rw,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,seclabel,relatime)
pstore on /sys/fs/pstore type pstore (rw,seclabel,relatime)
none on /sys/fs/cgroup type tmpfs (rw,seclabel,relatime,size=2920852k,nr_inodes=730213,mode=750,gid=1000)
none on /sys/fs/cgroup/freezer type cgroup (rw,relatime,freezer)
none on /acct type cgroup (rw,relatime,cpuacct)
tmpfs on /mnt type tmpfs (rw,seclabel,relatime,size=2920852k,nr_inodes=730213,mode=755,gid=1000)
/data/media on /mnt/runtime/default/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,multiuser,mask=6,reserved=50MB)
/data/media on /mnt/runtime/read/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,multiuser,mask=23,reserved=50MB)
/data/media on /mnt/runtime/write/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,multiuser,mask=7,reserved=50MB)
none on /config type configfs (rw,relatime)
/dev/block/bootdevice/by-name/system on /system type ext4 (ro,seclabel,noatime,discard,data=ordered)
/dev/block/bootdevice/by-name/cache on /cache type ext4 (ro,seclabel,nosuid,nodev,relatime,data=ordered)
/dev/block/bootdevice/by-name/persist on /persist type ext4 (rw,seclabel,nosuid,nodev,relatime,data=ordered)
/dev/block/bootdevice/by-name/dsp on /dsp type ext4 (ro,seclabel,nosuid,nodev,relatime,data=ordered)
/dev/block/bootdevice/by-name/modem on /firmware type vfat (ro,context=ubject_r:firmware_file:s0,relatime,uid=1000,gid=1000,fmask=0337,dmask=0227,codepage=437,iocharset=iso8859-1,shortname=lower,errors=remount-ro)
/dev/block/bootdevice/by-name/bluetooth on /bt_firmware type vfat (ro,context=ubject_r:bt_firmware_file:s0,relatime,uid=1002,gid=3002,fmask=0337,dmask=0227,codepage=437,iocharset=iso8859-1,shortname=lower,errors=remount-ro)
/dev/block/dm-0 on /data type f2fs (rw,seclabel,nosuid,nodev,noatime,nodiratime,background_gc=on,discard,user_xattr,acl,inline_data,inline_dentry,flush_merge,extent_cache,mode=adaptive,active_logs=6)
/dev/block/loop0 on /su type ext4 (rw,seclabel,noatime,data=ordered)
tmpfs on /storage type tmpfs (rw,seclabel,relatime,size=2920852k,nr_inodes=730213,mode=755,gid=1000)
/data/media on /storage/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=9997,multiuser,mask=7,reserved=50MB)
tmpfs on /storage/self type tmpfs (rw,seclabel,relatime,size=2920852k,nr_inodes=730213,mode=755,gid=1000)
OnePlus3:/ $

 

[fuzzylumpkin]

Ah, it did post that second time...

 

[Jerry Hildenbrand]

Excellent.

Thanks!

I'm trying to keep track of what phones are doing this trick so I know where to look when things go bad

 

[fuzzylumpkin]

No probs, happy to help.