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Premium Member
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Discussion Starter · #1 ·
What command do I use again to tell UNIX to do it's Nightly cleanups, or whatever it is.

ThanX

/sleepy miscommunication
 

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Tritium Glow
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the command is periodic followed by the script name[daily], [weekly], [monthly]

the command will look like this:

sudo periodic daily

prior to Jag it was

sudo sh /etc/daily [weekly], [monthly]

this gave you the verbose mode, not sure if it it still works in Jag as I have changed the crontab file to run the maintenance scripts at a time when my 'puter is on.
 

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Discussion Starter · #4 ·
macspectrum,
it is easier, but it also another application that I dont want, I would rather just run the commmand myself, or make an applescript to do it for me!
 

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Premium Member
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An App like OnyX or Cocktail might be more to your liking as it cannot only do the cron scripts, but empty caches, update_prebinding and repair permissions.

They are handy little apps.

--PB
 

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Premium Member
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Discussion Starter · #6 ·
what does it mean when you get a msg saying:

[emotionDV:~] emotiondv% sudo diskutil repairPermissions /
This disk cannot have it's permissions updated

:rolleyes:
 

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Tritium Glow
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My understanding is that "journaling" will not have much of an effect on HFS+ volumes. Works best on servers configured with UFS.
 

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On a quick lookup it appears that journaling offers significant stability and recovery advantages and apparently IS backward compatible to aid HFS+ volumes in a similar manner.
Maybe that's part of why Panther seems so bulletproof. The underlying system structure is better protected.
My guess this is an advantage for quick boxes like the G5 and may be a drag on slower systems adding significant overhead. :cool:



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Journaling offers no real speed enhancements, but it does offer mush in the way of stability. basically, journaling keeps track of what changes are about to be made and what changes have been made to files.

To paraphrase another source[1], Imagine a library, and each night a librarian goes around with a stack of books and puts them back on the shelves. when she is done she writes down in the log all the books she put back.

One night she is in the middle of putting the books back and she dies of a heart attack.

Now what is the replacement supposed to do? How is she supposed to find all of the books that were put back? She would have to check every book against the checked in and put back log, eventually finding that all those not on the list were the ones that her predecessor done the night she died.

Now imagine that the first librarian had carried a notebook around with her (a journal, if you will) that had a list of all the books to be put back and she marked each one off as she put it back. Now when she has that heart attack the new librarian just has to look at the notebook to see where to continue.

That's a journaled filesystem. It keeps detailed track of changes to files before and after they occur.

Filesystem corruption is very hard to have happen with a journaled file system (although not impossible), and if any does occur it is very easy to fix. Also, because there are less problems like corruption associated with journaled filesystems your productivity can and probably will go up because you don't have to worry as much about problems happening and they are faster to fix if they do.

With a journaled file system you should be able to start a huge disk write procedure involving gigs worth of files and then literally pull the power cord half way through and not see any issues, and on top of that under some implementations the disk write will start up again from where it left off when the system is rebooted (although I am not sure if Apple's implementation does this).

Some implementations also offer a history function where you can roll back changes to a file, which is very cool.

One thing to note about Journaling (at least under OS X 10.2.x) is that it does break FSCK. Probably though you wont need it anymore anyway. Also, it willl add some overhead to your write speeds but quicker systems probably wont be affected and from what I have read even older systems don't see that much of a lag.

If you have a RAID setup, journaling could very easily save your butt (especially on mirrored setups) because afterall, two drives are twice as likely to become corrupt as one.

Oh, and Apple did write it on top of HFS+ as well.

--PB

[1] source is Slashdot and also AppleInsider
 

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*bump*

I spent a long time writing this and then it fell off the main page. Just putting it back up for all to see.

--PB
 

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ehMac KungFu Master
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PosterBoy's report on journaling is essencially correct.

I enable Journaling on just about all the systems I install these days. I definetly use it on any servers and workstations under heavy load or with lots of files.
Here's a case in point:

A couple of years ago I was maintaining a network of 40 Macs in a design sweatshop on Netware 4 (don't ask, I couldn't understand it either). ANyhow, that Netware server would crash at least a couple of times a week resulting in about 2 HOURS of downtime while the file system went through a consistency check upon a reboot.

My linux servers (formatted as ext3 journaled) on the other hand contain way more files and data that the Netware server ever did and if I pull the plug or have a power outage those machines reboot, catch the filesystem problem, read the journal and keep booting in a matter of SECONDS. HUGE difference.

Same thing happens on the Xserves I setup. Journaling ON, always.
 
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