du vs df /jffs

[dineshgyl]

Why there is space difference between jffs between du and df?

/tmp/mnt/himani/entware/var/log# du -ak /jffs | sort -nr | head
3116    /jffs
980     /jffs/signature/rule.trf
980     /jffs/signature
848     /jffs/addons
728     /jffs/addons/shared-jy
564     /jffs/scripts
268     /jffs/.sys
264     /jffs/addons/shared-jy/d3.js
212     /jffs/scripts/arp
200     /jffs/scripts/arp/mhttp_arm64


/tmp/mnt/himani/entware/var/log# df -h /jffs
Filesystem                Size      Used Available Use% Mounted on
ubi:jffs2                44.5M      7.0M     35.1M  17% /jffs

I see this used goes upto 20M then reset backs to 3M.

 

[ColinTaylor]

On your router /jffs is a UBIFS filesystem. UBIFS is a compressed filesystem where free space is only an estimate. Write caching and garbage collection also have an effect.

 

[sfx2000]

On your router /jffs is a UBIFS filesystem. UBIFS is a compressed filesystem where free space is only an estimate. Write caching and garbage collection also have an effect.

Not really... bit more complicated, and has nothing to do with ubifs being compressed or not...

 

[ColinTaylor]

Not really... bit more complicated, and has nothing to do with ubifs being compressed or not...

Yes it's more complicated but the gist is correct. See here: http://www.linux-mtd.infradead.org/faq/ubifs.html#L_df_report

If you think otherwise then explain rather than ...

 

[sfx2000]

If you think otherwise then explain rather than ...

Perhaps you can further elaborate then - you seem to be on top of this...

 

[ColinTaylor]

Perhaps you can further elaborate then - you seem to be on top of this...

I provided a brief explanation of the problem and then linked you to the official documentation (with examples)...

You're the one that said I was wrong, so explain why...