log and delaylog for jfs version 4

[simone teles da hora_1]

Hi,

i?ve got a stratus machine, which use hp-ux 11.00. My file systems use jfs version 4 and im not sure what can i do with option log and delay log.

with option log, my file is safe if someone crash to happen in the moment to write (system call write)? Or the aim is just directories and file created?

thanks so much

simone

[James R. Ferguson]

Hi:

Start by taking a look at the 'vxtunefs' command: See vxtunefs(1M) and tunefstab(4).

Also, take a look at:

http://docs.hp.com/hpux/onlinedocs/os/veritas_admin.pdf

...JRF...

[Dan Hetzel]

Hi Simone,

Using 'log' (by default) all filesystem structural changes are logged to disk before the system call returns to the application.
This is the safest mode as every log will be completed in case of a system crash.

'delaylog' behaves approximately the same, but some calls wil return before the data is actually logged. This mode gives slightly better performance at the expense of possible data corruption in case of a system crash.

Unless you are in need of the utmost disk performance, I'd strick with 'log' as it's the safest mode.

Best regards,

Dan