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discofuel
Mar 6, 2010, 01:21 AM
I'm just about to make the transition from a PC with Cubase to a 27" i7 iMac with Logic and Pro Tools and wondering how best to set it up.

With my PC I've always partitioned the hard drive - should I do the same for my mac?



Fishrrman
Mar 6, 2010, 09:35 AM
Others will say no, but I say yes, do it, particularly if you're going to be recording audio and don't want to use a second drive in all situations.

I would suggest creating one (or more) "project partitions" that are relatively small in size. Just HOW small depends on your own experience with past projects. I've found that for my own projects, 6-8gig is fine (my projects are of acoustic audio, nothing much in the way of effects, up to 20 tracks).

By segregating your audio input to a relatively small partition, the drive doesn't have to go hunting all over the disk during the actual tracking. It also makes it easy to compact, defrag, and optimize the work partitions later on (iDefrag is the application to use for these tasks).

I also keep a larger partition on the drive (separate and apart from my "boot partition") which I "archive" completed projects to. Thus they are moved "out of the way" from all other disk activity.

So my hard drive actually has numerous partitions:
- Boot partition (contains system software, applications, etc.)
- Archive partition (completed projects)
- Project partitions (three or more)

I also use Cubase (LE4 version), works fine here. I generally record two tracks at a time and have no problems with latency, audio artifacts, etc. using the "project partition" setup above. Not sure if this will work if you're going to do, say, six to eight tracks simultaneously. But for two (and probably for at least four) no problems....

I haven't tried Logic or ProTools, so can't speak for those apps, either.

cube
Mar 6, 2010, 09:38 AM
No, because the disk will have to move back and forth constantly between the system and data areas.

ChrisA
Mar 6, 2010, 11:46 AM
I'm just about to make the transition from a PC with Cubase to a 27" i7 iMac with Logic and Pro Tools and wondering how best to set it up.

With my PC I've always partitioned the hard drive - should I do the same for my mac?

THe only reasons to partition a drive on a Mac (1) is to "contain" a set of file so they do not grown in size to take over the entire disk. Inother words you want to be sure to always have free space in the other partition. An example would be so that Time Machine can't use all of youre 2TB external disk. or (2) you want to put two different file systems on the disk, one HFS for Mac and mmay an PC file system in the other partition so you could share the disk with PCs. or (3) you want to be able to boot another OS (boot camp)or another verion of Mac OS.

The reason PC back in the 80's partitioned disks was because the primitive file system hada a maximum size limit, so you made partitions below that limit.

One good reason NOT to partition a disk is because you get less usable total space. Each partition eeds a certain minimum free space and with two partitions you double the space you can't really use. Mac don't work well with 99% full disks.

+1 on that perfomance issue too. Not only will the disk head have to move more but even worse, the outside of the disk moves the fastest, That's just due to geometry, the tangental speed is greatest on th outside of any wheel. So, only one partition can be in the "fast zone" Best to have one partition and let Mac OX manage where the data goes.

If you need to keep data archived or backed up buy a stack of external drives. Keep one at the office, one in a fire safe and one near the computer back not plugged in one as a Time Machine drive and rotate them around. A 1TB drive costs only $100 I make a habit of buying a drive every year and retiring my oldest external drive.

Fishrrman
Mar 6, 2010, 09:15 PM
Like I posted in #2, others will say no.

But my own experience over the last few years proves otherwise.

I wouldn't do it any other way.

musio
Mar 7, 2010, 09:21 AM
Don't worry about it.

If you had two disks, you could as you'd have one system and one audio with both independent read/write heads. Your audio drive could have a small scratch partition so the read/write heads wouldn't move as much.

You won't have any problems. I've recorded 8 tracks at once and played loads without any probs on an iMac.

bLiss
Mar 8, 2010, 01:27 PM
+1 on that perfomance issue too. Not only will the disk head have to move more but even worse, the outside of the disk moves the fastest, That's just due to geometry, the tangental speed is greatest on th outside of any wheel. So, only one partition can be in the "fast zone" Best to have one partition and let Mac OX manage where the data goes.

I've heard this argument in favor of partitioning the disk. For example, on a 500 GB hard drive, the hard drive must read the index and then search for one file that is perhaps anyplace on the disk among some 400 GB of used space. However, if the disk is partitioned into 100 GB segments, the index points to the file as being in the 3rd partition, sector # whatever, and voila faster file seek.

That reminds me, what of the "fast zone"? My understanding is the needle reads the index first so is there not still travel time involved from the center to the outside of the disk, whether or not the outer edge is covering more circumference in the same spin? My intuition says files closer to the center of the disk are more readily accessible.

Someone please correct me if I'm wrong because I'm getting a new hard drive myself and I've been confident that I should partition it in some organized manner.

ChrisA
Mar 8, 2010, 09:07 PM
I've heard this argument in favor of partitioning the disk. For example, on a 500 GB hard drive, the hard drive must read the index and then search for one file that is perhaps anyplace on the disk among some 400 GB of used space. However, if the disk is partitioned into 100 GB segments, the index points to the file as being in the 3rd partition, sector # whatever, and voila faster file seek.

That reminds me, what of the "fast zone"? My understanding is the needle reads the index first so is there not still travel time involved from the center to the outside of the disk, whether or not the outer edge is covering more circumference in the same spin? My intuition says files closer to the center of the disk are more readily accessible.

Someone please correct me if I'm wrong because I'm getting a new hard drive myself and I've been confident that I should partition it in some organized manner.

You forget that Mac OS X caches data in RAM. The index does not have to be read off the disk drive most of the time. Also in a single user desktop, unlike a server, what matter most is the "sequential" speed, that is, after you get to the large file you read it end to end. The server has to accept requests for many users and does bounce around more, But still on a modern system the most used data from the disk remains in RAM.

Also the OS will use an "elevator algorithm" This assumes read/write requests are generated faster then the disk can run and they back up into a queue. The system will re-order requests to minimize head motion, just like an elevator does not bounce around between floors chasing each call button but takes an up/down/up/down path. So "out of order command execution" greatly reduces the average access time. Disk head scheduling can be complex with many competing requirements. Any multi-tasking OS needs to do this or it's even WORSE than you describe with 5 apps all telling the disk head to read their file. The elevator scheduler sorts this out and minimizes head motion. Partition caus a gap of many empty tracks and cause the "elevator" to have to work a taller building with longer round trips
So reading sequential sectors is what matters This also explains why RAM helps so much, it greatly reduces disk I/O

This is not new. I think is was not new even when I was a Comp Sci major at UCLA in 1980. Remember UNIX dates from 1969. Mac OS X has direct linage to that 60's vintage code base. and many of the ideas (virtual memory and so on that UNIX used were developed for "Multix". which is even older. unix is a word play on multix and also a comment on why it's better.)

Those stories about what is "fast" and re-reading the index apply to old DOS and older Windows systems which were very primitive even compared to 60's vintage "real computers"

discofuel
Mar 8, 2010, 09:27 PM
You forget that Mac OS X caches data in RAM. The index does not have to be read off the disk drive most of the time. Also in a single user desktop, unlike a server, what matter most is the "sequential" speed, that is, after you get to the large file you read it end to end. The server has to accept requests for many users and does bounce around more, But still on a modern system the most used data from the disk remains in RAM.

Also the OS will use an "elevator algorithm" This assumes read/write requests are generated faster then the disk can run and they back up into a queue. The system will re-order requests to minimize head motion, just like an elevator does not bounce around between floors chasing each call button but takes an up/down/up/down path. So "out of order command execution" greatly reduces the average access time. Disk head scheduling can be complex with many competing requirements. Any multi-tasking OS needs to do this or it's even WORSE than you describe with 5 apps all telling the disk head to read their file. The elevator scheduler sorts this out and minimizes head motion. Partition caus a gap of many empty tracks and cause the "elevator" to have to work a taller building with longer round trips
So reading sequential sectors is what matters This also explains why RAM helps so much, it greatly reduces disk I/O

This is not new. I think is was not new even when I was a Comp Sci major at UCLA in 1980. Remember UNIX dates from 1969. Mac OS X has direct linage to that 60's vintage code base. and many of the ideas (virtual memory and so on that UNIX used were developed for "Multix". which is even older. unix is a word play on multix and also a comment on why it's better.)

Those stories about what is "fast" and re-reading the index apply to old DOS and older Windows systems which were very primitive even compared to 60's vintage "real computers"

Err... so I shouldn't partition?

bLiss
Mar 9, 2010, 02:37 AM
Err... so I shouldn't partition?

lol :)