Mac OS X Extended Journaled or Not ?

Journaling is the active defrag that Apple does to increase speed (and prevent data corruption). The most often accessed files are moved to the fastest parts of the drive on the fly.

TEG

TEG said:

Journaling is the active defrag that Apple does to increase speed (and prevent data corruption). The most often accessed files are moved to the fastest parts of the drive on the fly.

TEG

Click to expand...

Not quite.

Check out Apple's Documentation http://docs.info.apple.com/article.html?artnum=107249

Journaling actually can slow down a disk, as the OP was correctly told. Because each transaction must be recorded to the journal, there is a performance penalty when writing to the disk. Reading from the disk carries no such penalty.

Try a quick google search using "disk journaling" and "disk journaling performance". You'll find a few useful articles.

TEG said:

Journaling is the active defrag that Apple does to increase speed (and prevent data corruption). The most often accessed files are moved to the fastest parts of the drive on the fly.

TEG

Click to expand...

Not so much.

Journaling is used to prevent data corruption in case of sudden power outage, etc.

http://en.wikipedia.org/wiki/Journaling_file_system

The benefits outweigh any performance hits. Very few instances would see any difference.

Here's a KB article from Apple: http://docs.info.apple.com/article.html?artnum=107249

TEG said:

Journaling is the active defrag that Apple does to increase speed (and prevent data corruption). The most often accessed files are moved to the fastest parts of the drive on the fly.

TEG

Click to expand...

That isn't journaling. That is the auto-defrag & the hot file feature.

Journaling can slow down or speed up disk writes depending on the particulars. Unless you know exactly why you want it off, it is better to be left on.

Manually defragging your Safari cache is often a big speed win on 10.5. In Terminal, with Safari closed, run the following lines. If you have other user accounts, log out and back in as each account and repeat:

PLEASE NOTE :::: THE SINGLE QUOTES on THECACHE line are from the quote on the tilde(~) key to the left of the number 1 key. You must use the correct quote! The double quotes around Cache.db are the usual double quote from pressing Shift with the key to the immediate left of your Return/Enter key. Or, just cut & paste!

cd ~/Library/Caches/com.apple.Safari
dd if=Cache.db of=Cache.db2 bs=16384k
chown `ls -l Cache.db| cut -f4 -d' '` Cache.db2
mv Cache.db2 Cache.db
sqlite3 Cache.db VACUUM
cd /private/var/folders
THESAFE=`find . -iname "SafeBrowsing.db" | grep Safari|head -n1`
dd if=$THESAFE of=~/SafeBrowsing.db2 bs=16384k
chown `ls -l $THESAFE| cut -f4 -d' '` ~/SafeBrowsing.db2
mv ~/SafeBrowsing.db2 $THESAFE
sqlite3 $THESAFE VACUUM

You'll get some permission denied from find. Don't mind them.
ONLY FOR 10.5! Safari on 10.4 has a different cache structure.