What is journaling, if anything???

[mm]

I posted to an English ng, but their answer was writing in a journal. Now I think I'm thinking about some machining process, journaling??? Related to bearings???

What am I thinking of?

[krw]

Try definition #3.

[Dbdblocker]

It is what a journaling file system does before it commits data to the hard drive.

Wasn't it also a way to make a channel in wood or metal?

[mm]

Thanks. I had looked in dictionary.com and I see now it did give that but only in the context of a noun. Didn't pay attention.

There was also an M-W entry for journal bearing but when I clicked on that it said

journal bearing

To view the definition of journal bearing, activate your Merriam-Webster Unabridged FREE TRIAL now!

These are all still nouns, and I remember it used as a verb, maybe like dbdblockers says.

[krw]

That context is the same as keeping a daily journal or perhaps "Ladies Home Journal". ;-)

In wood, anyway, a such a channel is a dado (cross-grain) or rabbet (with the grain).

[Ed Pawlowski]

If you write in a journal bearing, chances are the friction will wear away the notes in short order. Talk to your accountant for a better journal.

[mm]

That might be what I've been thinking about. What DOES a journaling file system do before it commits data to the hard drive?

Maybe.

Ed, I keep thinking of my records ground to dust. Rather than a better journal, I'll try to find a better accountant.

[Tegger]

mm wrote in news: [e-mail]:

What's the context?

[RogerT]

I have the same question. What did you post to the "English ng", and what did the answer say about "writing in a journal"?

[Home Guy]

Journalling, as performed by an NTFS file system, sacrifices user data that was being written during an interrupted write operation for the sake of maintaining a "clean" file system.

Under FAT/FAT32, data that was being written during an interrupted operation can be salvaged, and until that salvage is done the file system continues to operate just fine because it suffers no real structural dammage in the process.

I had an NT-4 web server that would nuke 2 weeks worth of IIS log files any time the server lost power - even though IIS closed each file at the start of a new day. After the system came back up, the log files were still there, same time-stamp and file-size, but they were filled will null characters.

[mm]

I asked what journaling is. And most of their answers were about the noun journal. I think Home Guy figured out what I was thinking of. Thanks Home Guy and thanks all for the discussion of other meanings.

[krw]

A journaling file system makes a "journal" of the changes to the file, makes a copy of the file, then performs the changes. A bit is then set to indicate the new file is now the real file and erases the "journal" and the old file. The advantage is that "bit" change is atomic (either it happens or it doesn't

- can't be in between). That atomic write, if successful, completes the update. If power is lost or the system crashes, you still have the old file, uncorrupted, *and* the journal so the operation can be retried later.