Oh yes, so he did, my bad. Very interesting this is then! So how could you tell the Raptor was the bottleneck? And did you take into any controller cache? I'm quite interested in this.
I have serious doubts whether a 5 disk RAID 5 system will beat two disk RAID 0 for write performance. For pete's sake it's all on the original post. This guy has 2 disks in RAID 0 and it was lightning fast and then had 3 disk RAID 5 and it was dog slow. Same hardware, different setup, and it's slower, that's what you'll get with any controller.
Cache was not a factor due to dataset size (a copy of 50GB). The speed of the whole operation was equvalent to reading from the Raptor, and a copy from the first RAID5 array to the second array gave better performance than reading from the Raptor and writeing on the array.Both arrays consists of 5 500GB 7200rpm SATA harddisks. Can't remember make or model of his controller.
A 5 disk array with a good controller shall beat RAID0, if correctly configured.
Anyways there are certainly something terribly wrong with his configuration. If it takes seconds to read ID3 tags from MP3 files in WinAmp, something has gone horribly wrong. The best advice is to reformat and experiment with different parameters, until performance is acceptable - but with 3 disks he won't reach RAID0 levels, and without a dedicated controller, writespeeds won't be optimal.
If you are a heavy Oracle user (with those expensive licenses), with databases which aren't that big, but accessed intensively, then money won't be a problem. If money is no problem, a massive RAID 1+0 with 15k SAS or fibrechannel disks will certainly outperform RAID 5 with a similar number of disks (but sacrificing capasity). But here we are talking a very special situation, and even here it will difficult to recommend the added expense if money has any importance at all.
Exactly - RAID 0 is a questionable idea with two discs, but as it goes from questionable to bad, and on to atrocious when adding more disks.Not that I'd ever ever recommend 5 disk RAID 0. 8O
This is true but my original already-off-topic point wasn't focussed on using databases, I was just using it to demonstrate what I was saying about RAID 5 write performance being bad. At the end of the day, you should never implement RAID 5 if you are focussed on performance, only if you want a large reliable and cost-effective filesystem.
Exactly - RAID 0 is a questionable idea with two discs, but as it goes from questionable to bad, and on to atrocious when adding more disks.
Only in very special cases, have you only got one focus. Small highend Oracle databases where money is no object is one such case.
Generally RAID5 performs very well (not best) across a lot of usage scenarios, and starting with a good controller and 5 disks, it is also very performarnce/cost efficient. I am always balancing the requirements when making recommendations, and except for outlaying cases (very small systems or highend databases) RAID5 gives a lot of performance and capasity for the money. And it should certainly always beat single drives......
I have one 36GB SCA SCSI with a host adapter and two Western Digital Caviar 16MB 250GB. What is the IDEAL setup for performance on these 3 drives? I want pure, no punches pulled, screaming perdformance. (With what I have)
So I should install the OS on the SCSI and everything else on the two SATAs?
And even if the SCSI is not included in the stripe, I can still boot from it and use the SATAs right?
And would a PCI-e SATA RAID card be faster than onbaord SATA RAID? (eVGA T1 680i LGA775)
Well I have a 6 port PCi-E SATA RAID Controller. I also have a few more SCSIs. I have 2 15k SCSIs and 2 host adapters. What Should I do? How should I use the 2nd one? Paging file? I have 2gb of RAM so i turned paging off.
So I should install the OS on the SCSI and everything else on the two SATAs?
And even if the SCSI is not included in the stripe, I can still boot from it and use the SATAs right?
And would a PCI-e SATA RAID card be faster than onbaord SATA RAID? (eVGA T1 680i LGA775)
Would a SCSI with a host adapter be better for gaming?
Would a SCSI with a host adapter be better for gaming?
Yeah, but name someone who can afford a SAS drive and a controller card...
GOOD $HIT MAN! Better guard those cans... I am getting my SCSIs from work. Anyone wanna buy some? Free for me.