[Ti] Journeling.

[Glenn L. Austin]

on 8/5/04 3:02 AM, David DelMonte at ddelmonte at mac.com wrote:

> Hi all.
> 
> What does disk journalling provide?

Basically, a journalled file system provides an additional, smaller
operation to track changes made to the file system before the actual
operation is executed. After the operation is complete, the journal entry is
marked as complete.  Basically, the OS keeps track of what it's doing, kind
of "going to do this," "doing this," "done with this."

What it means to you is that if your computer crashes at some point, then
restarting the computer is much faster because all that needs to be done to
make the disk consistent is to play back the journal entries and execute the
operations.

> What resources does it cost?

Just some disk space and cost of some disk performance when writing.

-- 
Glenn L. Austin <><
Computer Wizard and Race Car Driver
<glenn at austin-home.com>
<http://www.austin-home.com/glenn/>