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ChrisFromCanada
Jul 18, 2004, 11:38 PM
So here is my new set-up, See sig for computer.
I have an external 80Gb for backup only and it is really noisy so I only turn it on for back-up. I also have an internal 80G and just ordered another 200G internal. So my question is what would be a good RAID 0 setup for me? I'm thinking partition the 200 into 120 and 80 then RAID 0 (stripe) the normal 80 to the partitioned 80 and use that for video and then use the ramaining 120 for system. Would this work? Or can I/would I be better off doing a raid with the 200 and the 80 togther.

Sorry if I am not making sence it is late. I will post again in the morning. :)

G5orbust
Jul 19, 2004, 12:57 AM
So here is my new set-up, See sig for computer.
I have an external 80Gb for backup only and it is really noisy so I only turn it on for back-up. I also have an internal 80G and just ordered another 200G internal. So my question is what would be a good RAID 0 setup for me? I'm thinking partition the 200 into 120 and 80 then RAID 0 (stripe) the normal 80 to the partitioned 80 and use that for video and then use the ramaining 120 for system. Would this work? Or can I/would I be better off doing a raid with the 200 and the 80 togther.

Sorry if I am not making sence it is late. I will post again in the morning. :)


Just RAID the whole thing. Youll get faster system performance (RAID 0 is the faster, but nonredundant one) as the hard drive will be both your scratch disk and your system disk.

Im not even sure you can RAID a partition with a full drive...

ChrisFromCanada
Jul 19, 2004, 11:14 AM
Just RAID the whole thing. Youll get faster system performance (RAID 0 is the faster, but nonredundant one) as the hard drive will be both your scratch disk and your system disk.

Im not even sure you can RAID a partition with a full drive...

lets say I do RAID the two drives togther and I put all my system files back on the new 280g raid will it put half on the 80 then the other half on the 200g and therefore filling the 80g faster than the 200g and because of that only give me better performance on the first 160g of files?

JFreak
Jul 19, 2004, 12:07 PM
i say do not raid.

it is enough for system to have a 15GB partition (!) and you can have the rest of the 200GB for your work. should be enough. and you will have that internal 80GB for "work backup" files. or for /Users folder.

raid0 is non-redundant, so if there is something wrong with the raid system, you will lose all data. that cannot be repaired. you would lose everything. raid0 is to be used only when you have large enough storage to back it up.

do not raid. think about the partitioning some other way.

(if it helps, i have a laptop that has a 60GB internal drive partitioned 15GB system 25GB users and 15GB storage. and external drive that has 50GB work partition and 100GB backup partition. the users partition is mounted to /Users and storage partition is mounted to /Users/Shared. external partitions are not mounted to specific directories, they just appear as /Volumes/partitionname as the partitions usually do.)

if you have pure speed in mind, remember that partitions in the beginning of the disk are located in the fastest part of the drive - partitioning wisely will give you significant speed boost as the drive will have to seek a lot less.

psycho bob
Jul 19, 2004, 12:09 PM
I think it is a bad idea. If you striped all three hard drives (2x80, 1x200) you would only be able to use 80Gb of the 200 drive the rest would be wasted. Making a RAID set out of an external and an internal will not be that fast and is even more risky than just striping two internals. If the external drive is FW400 the performance just isn't that great. Don't partition the 200 and then use part of it as a RAID set either. If the system and what ever application is using the RAID set need to access it performance will crumble.
I used to have my internals on my G5 raided I recently deleted the set, the gain just doesn't justify the problems it causes and some things are actually slower. When using software RAID the processor has to do a lot of work syncing data and working out what goes where this can take as much as 30% CPU power.
If your going to do RAID then get a hardware controller and some SATA drives. If you have a G5 and so only 2 internal bays get a 74Gb Raptor and install apps and the OS on to it, then place your home folder onto the 200Gb and also set that as the scratch disk.
(edit): just read your system. You can use up to 4 internals I believe in the G4, best to get a fast boot drive like a Raptor then get a hardware controller and 3 internal drives to stripe for what ever use you wish.

tomf87
Jul 19, 2004, 12:14 PM
I think it is a bad idea. If you striped all three hard drives (2x80, 1x200) you would only be able to use 80Gb of the 200 drive the rest would be wasted.

Not with RAID 0. RAID 0 will concatenate them together. In this case, that would yield 360GB. If you performed RAID 5, then you are correct.

psycho bob
Jul 19, 2004, 12:19 PM
Not with RAID 0. RAID 0 will concatenate them together. In this case, that would yield 360GB. If you performed RAID 5, then you are correct.

When you stripe the data is split directly between the hard drives. If all 3 drives were striped together the 2 80Gb drives could be filled leaving 120Gb on the 3rd drive. You cannnot continue to stripe if the other drives are full. RAID 0 is only 100% efficient if identically sized disks are used.

maxvamp
Jul 19, 2004, 12:33 PM
One thing to mention...

If you are using the Apple OSX utilities, you can only use entire drives ( no partitioning ).

If you wish to partition parts of a drive for RAID 0 or 1, you will need SoftRAID. If you want RAID 5, you need FWB's RAID Toolkit ( works well ) .

Max.

ChrisFromCanada
Jul 19, 2004, 05:15 PM
Thanks for the tips

Let me get this right in order to RAID 0 two drives togther they have to be the same size (or only part of the larger drive will be recognized)? Also I forget to mention the external 80G is a shared family backup drive so I con't use that in a RAID but I guess it is not very effiecent anyway.

I will probably end up just using the internal 80g for system, Mp3's, downloads, games etc. Then use the 200g for Video and the external 80 for family back-up.

Also the 200 I bought was a new Maxtor with warranty for about $145 taxes and shipping included. And I talked to someone recently who said I got ripped off because he can get a Western Digital for $130 and they are much better and feature a 3 year warranty. I thought the consensus here was Maxtors are better anyway thanks again. :)

maxvamp
Jul 19, 2004, 05:40 PM
You could RAID the 80s ( one internal / one external ) together for a 160 GB volume. You would need to backup all data from those drives to convert them to RAID.

Since you would end up using it for MP3s and backup, I am not sure that it buys you anything more than a bigger catastrophy when one of the two drives dies.

Lose one drive, lose all data from both.... Bad thing about RAID0

Max.

Windowlicker
Sep 12, 2004, 01:22 PM
I was searching for input about RAID and found this thread (one of many of course). I'm probably buying a 2nd HD for my G5 (not very soon though maybe next summer when I get back to work between my studies) and would like to know, if I can speed up my system by raiding the two drives?

I would probably buy a 400Gb (or larger) HD and partition it to two parts (first part being a 160gb one, just like my current hd), the other part being for RAID and the other one for temp. storage.

And the RAID would be done by software (OSX). Any point doing this? Some better ideas maybe? I need more space anyway.

kugino
Sep 12, 2004, 01:33 PM
are you guys saying that the two HDs need to be the same size for RAID? what are the advantages of this? i'm going to buy a G5 2.0 w/the 160 GB SATA and was going to buy another 250 and use RAID. is this a bad idea?

(p.s. i'm going to buy it from an apple retail store so the BTO 250 SATA isn't an option for me...i have a discount at the store so no online purchase)