AIX6 - JFS2 "no log" option

AIX JFS2 with no log:


JFS2 filesystem with "no log" option will perform faster than "with log" option.

We can test this by doing the following exercise:

Create two filesystems,

#crfs -v jfs2 -g rootvg -a size=1G -A yes -a isnapshot=yes -m /red
#crfs -v jfs2 -g rootvg -a size=1G -A yes -a isnapshot=yes -m /blue

now open 2 different consoles one for red and another for blue,

mount one with "no log" and another "with log" option as below,
on first console:
#mount -o log=NULL /red

try to create more files by using a script and note down the time.

on second console:
#mount /blue

try to create more files by using a script and note down the time.

Now you can see that the filesystem without log option is creating a files 60 times faster.

Conclusion:

1. We can use this "no log" option in our ftp directories and where we have original copies are in different location/machine hence we can save significant time.

2. Where we can copy the data from one disk to another new disk (thousands/millions of files) then we can create a filesystem with "no log" option and start transfer the files. once the transfer completes then we can enable the "log" option and remounting the filesystem so that we can save more time.