Data Transfer (again) From Ext. Hd Options

[zaaresh]

Hi there helpful people,

lately i was asking lepetitmartien about recording and saving data on internal hard drives.
my prod. partner and me, we bought 3 hard drives: 1 Samsung 7200 400GB 8MB Cache and two Seagate 7200 320 GB 16MB. The Power Mac is: G4 MDD 2 x 1,25Ghz , 1GB RAM

- We are about to do a data transfer from an external firewire disk (LA CIE 160GB) which was formated and used on OS 9.2. - and there´s the problem nr 1: while trying to copy data - in this case samples from the Sound Banks (Battery, Xtreme Samples, etc.) , mostly aiffs and waves, we discovered that the data size of the copied samples is different to the original size on the external drive.

Anyway: copying succeded, and i can use the samples in LOGIC projects - but what´s the matter, do we use kind of reduced quality samples (??) or is it about a data information problem (while pressing Apple + I) because the LA CIE Drive has another format? what to do to get the right size ?


- The second question starts in LOGIC (version Logic Pro 6.4.) but is as well a Copying problem, I suppose: (I placed this question in the Software / Logic section as well, so please ignore it, if you think it´s in the wrong place)

while trying to save Logic songs as "projects" from the external to the internal drives - although i selected "copy audio + sampler instruments" the programm refuses to copy data from the external hard drive, for ex. it doesn´t copy Battery 2 samples to the project folder - so : the samples cannot be found while the external drive is off.

hope you didn´t fall asleep while reading this post ... , hope anyone can help!
thanks ,

milosz

[lepetitmartien]

You're right about the Logic stuff, one question per thread and things are neet

Now, can you tell me one thing. Are you saying that the files after being copied have shrink? Have you looked into the right part of the info window?

File size is displayed twice in the window, there's a number right after Size, for example 76KB, which is the real estate occupied by the file for the file system, it's a multiple of the drive block size used in full plus the one partially used by the file, as file size even if using their blocks in full, may surely not use the last one totally, but no other file will be written there in this last block. So this first number is a direct multiple of the block size.

There's a second number, for example here, 76693 bytes. this one is the real size of the file. That's the real estate effectively used by the file, no blocks here.

If you checked only the first number, yes, it can't be the same, as block size depends of drive size and format. If you checked the second numbers, it should be the same. If you checked the second numbers and these are not the same, then there is a problem.

Another issue I see: will this drive be used in OS X only? If so, why have you not formatted it beforehand in OS X? In Firewire (if it's the case) it is perilous to move drives from OS 9 to X and back, best is to keep things as separate as possible, and have the drives formatted in OS X to be new, fresh and pretty. If you need to move it between OS 9 and X, format it in OS X, ask the Utility to install the OS 9 driver too and pray (never ever trust the drive, so back up before if you have to move it back and forth).

[lancet]

If you checked only the first number, yes, it can't be the same, as block size depends of drive size and format. If you checked the second numbers, it should be the same. If you checked the second numbers and these are not the same, then there is a problem.

maybe this isn't the issue but, make sure you format HFS plus , not HFS.

generally speaking.....
HFS+ has a fixed block size of 4k.
HFS has a fixed maximum number of blocks so the size of the block varies according to the size of the volume.

in a forked file system, like OS 9 uses , the data and resource forks are separate and require at least one block for each of the forks. SO, on an HFS+ volume, a blank text file (no resource fork) will be 4k on disk, a 5k text file will be 8k, a 9k file would be 12k and so on .

on an HFS volume greater than 1GB the blocks will be large. a single block is 16k and on a 10GB volume the block size is 160k (appox.)

any file with a resource fork would require twice the number of blocks.

Ce message a été modifié par lancet - lun. 29 oct. 2007, 16:22.

[lepetitmartien]

You're right lancet, but block size can be of any size in HFS+ if you want to, just format in the terminal Now as not everyone will do so, it's fixed block size.

For whose who wonder the interest of changing this size, take a drive used only for large files, like audio or video, where you stream or record loads. You'll save time and headaches to the drive controller if blocks are big. Big blocks, less blocks, smaller databases for allocation, time saved, drive a little faster/responsive. The "waste" is marginal given the file size. It's of use more critical on heavy hard drive jobs like video work.

By the way, not using HFS+ since OS 8.5 is a bad idea… from personal experience.