I don't have numbers to back up the statement, but using HFS+ non-journaled is a good idea in certain volumes that require absolute speed, without worrying (too much) about a possible "data loss" or "data corruption" in case of power failure or similar.
When is using HFS+ Non-journaled a BAD idea?
External (USB, FW, ESata) drives that are connected and reconnected often: It's usually a bad idea, since these drives tend to be accidentally disconnected very often and or their power sources unplugged.
Partitions where data integrity is important and protection from an unexpected power loss is a must. (Documents, Music, Videos, Backups, etc).
When is using HFS+ Non-journaled a GOOD idea?
Scratch, Temp, trivial storage and similar drives and partitions, where speed is > data integrity in case of power fail. You want your Final Cut scratch volume to be non-journaled (you do have an UPS anyway, don't you?). You want your Photoshop temp to be non-journaled. Drives to copy stuff around (a Pen drive for example if you take care of properly ejecting).
Any other drive that requires portability and compatibility like you correctly pointed out.
Remember, maintaining the journal adds a small overhead, but the benefit in case of improper volume dismount are important, no only to avoid a full disk "scan" at startup or re-mount, but also in terms of making sure that data is not corrupted in the first place.
Mounting a non-journaled drive that has been incorrectly unmounted, will cause a fsck scan, whereas the journaled drive will be able to be up and running in a shorter period of time (scanning the journal and applying uncommited transactions).
Regarding Speed and tests, I don't have much info to back up the above claim, however, as far as I know the speed difference not only is very small and even hard to notice, but in some case Journaled filesystem is faster than non-journaled.
Turn out that despite the overhead of the journal, some operations can be made asynchronously in the Journaled drive, whereas the non-journaled version has to perform things synchronously.
For reference I googled a little bit trying to find an old comparison (the numbers are probably valid since HFS+ hasn't really changed much since their first iterations in OSX, other than adding Inline Attribute Data records, and access control list file security and maybe something else.
Here's the website with the charts:
Comparison Between HFS+ Journaled vs HFS+ Non-journaled
TL;DR:
The file copy/duplicate/copy sequence
was pretty much equally fast for both
journaled/non-journaled HFS. The same
sequence with the folder was again
somewhat faster with the journaled HFS
(emphasis mine)
Conclusion
I am somewhat surprised to see the above results, as I was kind of convinced that using Non-Journaled was really faster for some operations, but apparently the little cases where it can make a difference, it's overweighted by the "safety" of Journaling.
Griffo is correct. Now in your scenario, the difference boils down to the following:
- if you pick
/bin/login, then this program will check in the user database what your default shell is and run that shell as a login shell, thereby invoking the rc files that are run only when the shell is run as a login shell (in case of bash those are /etc/profile, ~/.bash_profile, ~/.bash_login and , and ~/.profile.
- if you pick
/bin/bash, that shell will be executed as a login shell, independently of what shell is set in the user database. This can come in useful when the shell in the user database does not work properly, or you want to be able to use different shells.
As per the comment by Chris Page, the shell is run as a login shell in both cases.
If you have not changed your login shell from the default, which is /bin/bash, and you have not changed the rc files of this shell, then the difference will not be noticeable.
Best Answer
Most of these codecs you can read more into by doing Google Searches on them. I will try to summarize some of this for you:
Video codec is the traditional QuickTime codec used by Apple, going back a very long time. The quality is good, but it takes up a lot of space as it uses relatively little compression.
H.263 was developed for use in early web applications. Flash and RealVideo were two very popular web delivery mechanisms that utilized this system. It essentially is an update to the MPEG-2 encoding frameworks used on DVDs.
H.264 is an update to H.263 and offers even more space efficiency based on the quality. The overall concept of this codec (as well as many others) is to provide a full frame every x number of frames, and in the intermediate frames, to simply record the changes that have occurred from the previous frame. So if you have a frame of a person walking with a still background, only the data of that person's movements are recorded.
DV - PAL is a format optimized for outputting onto DV (digital video) tape, and PAL means it is designed for the European standard (vs. NTSC which is the broadcast standard in the United States).
Animation is a format, similar to H.263, but optimized for animation footage, where there will be many areas of the solid color. It also supports an alpha (or transparency) channel, which allows footage encoded in this method to be layered over other footage.