about to RAID
im going to raid 3 harddrives, they are all the same model, the maxtor 5400rpm, 80 gig harddrives 2mb buffer...will raiding them show me ANY improvement?
Also, how should i raid them...which array do u guys suggest? I want the best performace possible.. what do u guys say? and yes i know about the raid page that spinner put up....im asking it for my specific case..
Also, how should i raid them...which array do u guys suggest? I want the best performace possible.. what do u guys say? and yes i know about the raid page that spinner put up....im asking it for my specific case..
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Yes, you'll see a performance increase.
Put another way, if there is an average 1-in-20 chance (5%) of a given drive glitching out, in a three-drive Raid 0 array the chance rises to greater than 1-in-7.
Doesn't have to be a hardware failure, either. As far as your OS is concerned, your MBR is dependent on none of your drives getting a little scrambled.
This isn't meant to scare you off, but if backing up "240 gigz of shiznet is not ez" then you need to plan ahead for future backups. I know that you have a couple of comps in your folding stable, maybe getting a whopping-big 160GB drive for data backup (and doing it regularly!) would not be a bad idea. My happiest experiences with Raid were when I ran a weekly incremental backup of all of my data files to a non-Raid disk on another computer. The performance increase is well worth it - so long as you still have the peace-of-mind a secure backup brings.
Good Luck - you'll have fun with it!
PS - You ROCK dood! (Inside joke
Only warning - I have had trouble getting the backups to run as scheduled. Scheduling them is easy enough, they just don't always run. I think this is because I have been pretty aggressive about disabling frivolous services. I guess one of them is not so frivolous after all...
I'll do some research to see if I can find a more comprehensive answer. In the meantime, even running manual scans is quite easy. I regularly back up about 8GB worth. It only takes about 20 minutes across the network.
Edit: GHoosdum beat me to it will I was doing my four-fingered typing.
Question 1: Set stripe to 16, where do I find cluster? There was no option for cluster size, using the Intel ICHR5 SATA RAID Controller. 1b. Does this have anything to do with formatting the drives in Windows, where it asks in a drop down for "allocation unit size"? Either way, I formatted to default on the 2 large partitions (7G for OS, 29G &32G for balance), but they have nothing on them so a fast answer will allow me to reformat if there's a better option.
**EDIT** Below problem solved
Problem 1. - probably motherboard/bios specific. The RAID array is 2 Raptors but I also installed a WD 40G JB drive for storage/backup/swap. It's seen in the bios - but not in WINXP PRO. Asus P4C800-E Deluxe.
**EDIT** I had the jumper on Master on this drive, changed it to CS and reconfigured boot devices in bios. Now recognized correctly in Windows.
"Does this have anything to do with formatting the drives in Windows, where it asks in a drop down for allocation unit size?"
You got it chief.
If you have PQMagic you can change them with your data intact. If not, just reformat and set the desired cluster size.
**EDIT** OK default is 4096 Bytes, except on my 2G Swap File partition, where it is 2048, I'm guessing due to the overall small size of the partition. Is consensus still to put the swap file on a drive OTHER THAN the OS drive? ie, OS is on RAID pair, swap is to go on the IDE WD.....
Since you already have the 4K clusters, benchmark that. Then I'd try 32K clusters. 16K stripe means each cluster will be evenly shared between the two drives; theoretically the raid will double your speed. Since each 1/2 of the cluster can be read simultaneously you'll get a 32K read at the same speed it would normally take to do a 16K read. You won't quite get that, due to system overhead.
Theories aside, real-world performance depends on a multitude of factors. The only way to be sure is through the trial-and-error method. That's where Partition Magic comes in handy. Do a clean install, defrag, bench, then resize clusters and repeat. It's a bit of a pain, but worth it in the long run. Once you know your system's "sweet spot" you're off to the races.
EDIT: Once you finish all that, you can repeat the process using different stripe sizes. It'll keep you out of trouble.
Put simply, any Raid 0 is likely to be faster than no Raid at all. But don't take my word for it...
I think you can find the info here.
RAID 0+1 (also known as 10) = best of both worlds!
To make sure the mainboard only see the drives i want it to see when i install them, i throw the other drives out or just unplug the power from it/them.
Set the drives to cable select and boot so you can enter the Raid bios. While in there, create a striped raid 0 array and select 32 as the stripe size.
Reboot from the bootable Partition Magic disk this time and in there, you will se that you have one array instead of two drives. In here, you can create as many partitions as you need and you can also create them in different clustersizes. You have to format the partitions and i suggest formatting the partitions in a clustersize of the same as the stripe, 32 in this case.
When that is done, reboot into the mainboard bios and remove the PM disk. Set the bios to boot from the cd and put in the OS cd and this is the important thing, HAVE THE RAID DRIVERS ON A DISK IN THE 3 1/2 drive ready.
When the first blue ugly windoze screen comes up and says on the bottom of the screen, "Press F6 for scsi or raid drivers" (or whatever it says), do that and follow the instructions so that the drivers gets installed before even trying installing the OS on the array. After this, it's just another Windows install, you just have to tell on which partition to install the os as usual.
As you can see, this little "how to" is built on the facts that you either have a raid-chip onboard or a PCI-card with raid capabilitys on it. I have never used or installed raid on an integrated raid, but i suspect it's exactly the same procedure except that the raid bios may be integreated into the mainboard bios instead and you choose what type of array/stripe size you want to use in there instead of on it's own bios.
Finally, the discussion of which stripe/clustersize is best, fastest or safest is an endless discussion. But 32/32 or 8/8 have always been the fastest for my two 80GB Western Digital JB's and i think i have tried all the combos. That doesn't mean that you have to use the same combo though.
This is how i would partition an Raid 0 array:
1, Bootpartition 150mb
2, OS 1 5 GB
3, OS 2 5 GB
4, Swappartition (up to 3 gig depending on how many OS and how big swapfile you use)
5, Programs and games
6, Temporary files and temporary internet files 1 GB
As you can see, i won't have any storage partition on a Raid 0 because if i loose the array, i will loose the lot. I can live with loosing all the above partitions but not any important data. The important data will be on another drive which will be the last thing to install when all this is done.
Finally, install a benchmark tool called ATTO and start taking readings on how the array do. Note that benchmarking an empty partition doesn't give any real life readings so benchmark the partitions that are in use the most. Also note that the benchmark numbers can differ a lot on different partitions even if the same stripe/cluster combo is used. That is because the middle part of the disk is in most cases the fastest part of the disk.
Just my 2 pesetas, this have always worked for me and given me some nice numbers. I am sure Tex will jump in from here and he is the man when it comes to this stuff.
Good luck!
Mac
And no, it looks terribe.
Don't forget to turn off your F@H.