Optimal data distribution on several HDD's

[AINTD]

Hey guys, it's me again. :D

I have finished building by bro's PC, turned out a candy, I love it and would envy him if it was not for the knowledge that I'm about to build and even better one for myself. :p Anyway, it turned out great and I think he'll be happy using it.

My questoin is more of an opinion than a technical: if you had the following array of HDD's, how would you have used them ... I mean, where would you install Windows, games, apps, etc. ... would you use RAID?

2 x 74GB WD Raptor @ 10k RPM SATA
1 x 250GB WD 7200 RPM SATA

[RotorHead]

Hey AINTD, I have almost the same drive configuration.......

2x 74 Gig Rapters and a 300 Gig WD

I have the 300 formated with 2 partitions, 40Gig for the OS and the rest for storage

The Rapters are in a RAID 0 configuration with 2 partitions, one for games and the other for media files

I decided to put the games on the Rapters, just because load times on startup and between levels is alot faster due to the large file sizes.

[AINTD]

I currently have the RAID 0 between Raptors and have Windows, games and all apps on it. Use the 250GB drive for storage, backups, etc. ... Since I'm going to do a full wipe when I'm done upgrading I thought perhaps there's a better way))

Is it not critical that Windows is actually on a "slower" drive? Also, does having Raptors in RAID "slow" them by any chance? It should'n since each HDD is writing/reading half the data compared to if it was one physical disc, just wondering) And why a separate "small" partition for Windows?

Thanks for your response! :thumb:

[RotorHead]

It's not critical at all for windows to be on a slower drive, you can have it on which ever drive you want. If you put it on the RAID, you will see a small increse in performanc.

The main thing with a RAID setup is file size and the amount of file transfers that occur. RAID 0 really shines when you have large files and transfer them alot, like what you would see in a file server that is on a small office network. The OS typicaly has smaller files and only transfers when needed, so you don't see as much of a performance gain. the times that you will notice an improvment are when you defrag, Virus check, load large games, or work with large media files.

Having said that.....If you are going to use the RAID to house your OS, then a smaller block size should give better performance. The block size can be established when you create the RAID array.

[AINTD]

I see ... I think I'll make two partitions on RAID 0 - one for the OS (some 5GB) and the other for apps/games (the rest). At any rate, whay block size do you think is adequate? Meaning, RAID creation utility offers one by default I think, but how much smaller can I make it ... just don't mess the things up. :D :D

[RotorHead]

I think most of the RAID utilities default to 64k block size, which you may want to change up to 128K, that should work out good.

I would also give windows at least 20-30Gig for its self.

[AINTD]

If you are going to use the RAID to house your OS, then a smaller block size should give better performance.


I think most of the RAID utilities default to 64k block size, which you may want to change up to 128K, that should work out good.

Errr ... kind of missed that ..? :D

[BGP Spook]

O boy.

Here is an idea.

If you are going to make a partition just for windows then why don't you figure out how many files windows has and how big the windows folder is.

Say you have 1000 files(HA!) and the foot print on your drive is 1 gig(HA! HA!).

You divid the number of kilobytes files by the number of files.

1024 Megs in a Gig.
1024 K in a Meg.
So 1048576 K in a Gig and 1048 KB in the average file.
So a 128K cluster size(maybe even 256K?) would be better(faster?) in general than 64K cluster size.

Be warned that the bigger you make your cluster size the more space you will wast.

My windows directory has 18,666 files and takes up 3.66 gigs which works out to ~205K per file average. So it would appear I would benefit from 128K cluster size as well.

[RotorHead]

You :rock: BGP.....

I learned something new today :o.....I never actualy thought of doing that, and it makes perfect sense...... :yup: :yup:

[Just Learnin']

O boy.

Here is an idea.

If you are going to make a partition just for windows then why don't you figure out how many files windows has and how big the windows folder is.

Say you have 1000 files(HA!) and the foot print on your drive is 1 gig(HA! HA!).

You divid the number of kilobytes files by the number of files.

1024 Megs in a Gig.
1024 K in a Meg.
So 1048576 K in a Gig and 1048 KB in the average file.
So a 128K cluster size(maybe even 256K?) would be better(faster?) in general than 64K cluster size.

Be warned that the bigger you make your cluster size the more space you will wast.

My windows directory has 18,666 files and takes up 3.66 gigs which works out to ~205K per file average. So it would appear I would benefit from 128K cluster size as well.


BGP are "block" and "cluster" sizes being confused here as regards RAID? Cluster size has no affect on space to my knowledge. :scratch:

[Just Learnin']

*Bump for BGP*

[BGP Spook]

I may be confusing these terms.

When Rotor referes to 128k block size I believe he is refering to the Raid equivalent of cluster size.

http://www.tweakxp.com/article37042.aspx


A cluster is the smallest allowable logical grouping of data on a hard drive(s).

[Just Learnin']

Not sure going by your reply, did I spank you or not????!!!! :lol: :mischeif: :hide: :deviltail Is the thread not aimed at stripe size? :scratch:

Excerpt from: searchwincomputing (http://searchwincomputing.techtarget.com/tip/0,289483,sid68_gci1039834,00.html)


Many third-party utilities, such as Powerquest's PartitionMagic, allow a user to change the cluster size of a partition non-destructively. Since larger cluster sizes do make disk access faster, many people may think the best thing to do on a big partition with big files is just to ramp up the cluster size as far as possible -- up to 256K. Unfortunately, this isn't always the smartest thing to do, as many other third-party utilities aren't designed to recognize NTFS clusters larger than 4K. Many defragmentation programs, for instance, cannot work correctly when confronted with a non-standard cluster size. If you plan on using third-party disk tools, or if you're planning on creating RAID arrays or mirrored disks, don't edit the NTFS cluster size by hand or you'll create problems you may not be able to resolve easily.

[BGP Spook]

That was my thought but now I am not sure I am speaking rightly on the matter.

EDIT: Infact, I am now only left confused. :scratch:

[RotorHead]

Sorry, I get confused at times.:beat: :beat:

I believe Stripe size is what I ment.......:coocoo:

Please whip me at your earliest convenience........:o :o

[Just Learnin']

Please whip me at your earliest convenience........:o :o


Why should you have all the fun?! :chit:

[BB_One]

Stripe size: The size of the block of data that it will be cut to;

File of 256K in a striping array of 64K, will be split in 4 blocks of 64K and place on 4 different drives if 4 drives are in the array.

Efficiency of the drive(s) is directly proportional to the way it was formatted ; ie: clusters. If clusters are 4k, it will take 16 clusters on each drives to accomodate the storage. But hard Drive mechanisism (seek/read/write) will have to perform 16 operations on each drive and said operation will more then likely not be linear or if you prefer the data will not be contiguous. ( Hence might require regular defrag )

If cluster are too big, ie: 128k , 1 cluster will be used to store 64k of data while the remaining 64 k on that cluster will be unused (wasted), hence reducing the data storage capacity of the drive. But hard Drive mechanisism (seek/read/write) will have to perform ONLY 1 operation on each drive. Data of that file on that drive of course will not be fragmented.

Understand what you plan on storing on your hard drives, one sizes DOES not fit all, day to day gamer versus a video encoder handling large size file, do not have the same striping or cluster requirements.