NCQ vs Perpendicular Recording

[ryan256]

I will be upgrading my server's storage if I win an eBay auction for a very nice SATA RAID controller. I'm looking at 2 different drives to use for storage: Seagate ST3500641AS or Seagate ST3500630AS. Only real difference I can see in these drives besides price is ST3500630AS supports perpendicular recording whereas ST3500641AS supports Native Command Queuing. I'm planning on using 3 of them in a RAID5 configuration. Is perpendicular recording really worth the $75 price difference for 3 of these drives?

Which would you choose??

 

[gramboh]

I'm pretty sure all Seagate 7200.10 500GB drives are perpendicular recording and support NCQ (as part of SATA2)? Unless I'm missing something? I hope mine do.

 

[bob4432]

it has shown in different benches (search the storage portion of anandtech) that ncq doesn't do much for sata stuff. basically you are comparing a 7200.9 drive to a 7200.10 drive. the 7200.10 drives did have really good str rates, but that was about it. if i were you, i would search around for some 7200.9 vs 7200.10 benches and see if it is worth it. i would say that for 3 drives it is not worth $75 if that is the only difference, but i remember people not liking the 7200.9 drives for some other reason - search and find out why...sorry i can't remember

 

[Pariah]

Neither. I don't know where the theory started, but perpendicular recording is not a performance feature. It does not improve drive reliability, or improve a hard drive in any other way really. The only purpose for perpendicular recording is to squeeze more data onto a platter which may or may not increase performance. Look at the Cheetah 15k.5. The only high RPM drive using PR. The drive has out of this world STR numbers which translate into absolutely abysmal desktop performance numbers. If you are looking for a high performance drive, neither NCQ nor PR should play any role in that decision. Simply looking at the numbers, Seagate has made the worst performing drives for a few years now, and being the only drive maker using perpendicular recording has done nothing to change that.

 

[Rubycon]

The 15k.5 is not a desktop drive.

 

[bob4432]

Originally posted by: Pariah
Neither. I don't know where the theory started, but perpendicular recording is not a performance feature. It does not improve drive reliability, or improve a hard drive in any other way really. The only purpose for perpendicular recording is to squeeze more data onto a platter which may or may not increase performance. Look at the Cheetah 15k.5. The only high RPM drive using PR. The drive has out of this world STR numbers which translate into absolutely abysmal desktop performance numbers. If you are looking for a high performance drive, neither NCQ nor PR should play any role in that decision. Simply looking at the numbers, Seagate has made the worst performing drives for a few years now, and being the only drive maker using perpendicular recording has done nothing to change that.

didn't the article with the TB hitachi state it used pr? i have a 15k.5 and will say that i have been looking for a good deal on a mas/mau or max fujitsu as my os/app/boot drive and leave the 15k.5 as more of the storage/temp dir drive(i could sell the 15k.5 but i got such a good deal on it i will probably never find a deal like this again, so i will keep it )

 

[myocardia]

Originally posted by: Pariah
Neither. I don't know where the theory started, but perpendicular recording is not a performance feature. It does not improve drive reliability, or improve a hard drive in any other way really. The only purpose for perpendicular recording is to squeeze more data onto a platter which may or may not increase performance. Look at the Cheetah 15k.5. The only high RPM drive using PR. The drive has out of this world STR numbers which translate into absolutely abysmal desktop performance numbers. If you are looking for a high performance drive, neither NCQ nor PR should play any role in that decision. Simply looking at the numbers, Seagate has made the worst performing drives for a few years now, and being the only drive maker using perpendicular recording has done nothing to change that.

Where did you come up with this crap? According to Anandtech, the Seagate 7200.10's are faster than all desktop drives, besides the Raptors.

 

[Pariah]

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau, which are both a generation older than Seagate's 15k.5, yet both trounce the Seagate in workstation performance as well as beat all SATA drives outside of the Raptor. The Maxtor is still faster than the Seagate in server performance too, with the MAU slightly behind the 15k.5, so it isn't like Seagate sacrificed workstation performance to develop world beating server performance. Seagate simply doesn't produce performance leading drives, which is probably why they went out and bought Maxtor, who could.

didn't the article with the TB hitachi state it used pr?

Yea, but you can't buy it yet unless you buy a Dell. There are portable drives that use PR as well, but currently Seagate is the only company selling standard ATA/SCSI drives using PR.

 

[Zepper]

Yes, a side benefit of PMR is a faster transfer rate as up to twice the data passes the heads in the same amount of time. Yes the Hitachi TB drive uses PMR. I've heard that they can get up to 250GB/platter but cranked it back to 200 for the TB drive to insure reliability. So if they weren't so conservative, they could have left the gate with a 1.25 TB drive... They are already available in some top end Dell and Alienware boxes and are supposed to hit gen. dist. in two or three weeks. Not that I'll ever need anything like that. I barely need an 80GB drive right now but I have 240GB on hand - just in case.

As was said above, all PMR SATA 2 drives also support NCQ. Most single users have no need of enabling NCQ, so just leave it off or Disable it. Depends on your application whether you need the extra transfer speed of the 7200.10. I have also read that the 7200.9 series has performance issues - I think the 7200.7 series are as fast or faster.

.bh.

 

[ryan256]

Originally posted by: Pariah

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau,

And all of those drives are SCSI and run into some serious money. Maybe I should have been a little more clear in the OP. This is for a personal data, file, web, ftp server. NOT an enterprise production environment. At most there will be 5 people using this server not 500. I was mainly wanting to find out if there would be any real difference in these 2 Seagate drives when put into RAID5 configuration.

 

[bob4432]

Originally posted by: Pariah

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau, which are both a generation older than Seagate's 15k.5, yet both trounce the Seagate in workstation performance as well as beat all SATA drives outside of the Raptor. The Maxtor is still faster than the Seagate in server performance too, with the MAU slightly behind the 15k.5, so it isn't like Seagate sacrificed workstation performance to develop world beating server performance. Seagate simply doesn't produce performance leading drives, which is probably why they went out and bought Maxtor, who could.

didn't the article with the TB hitachi state it used pr?

Yea, but you can't buy it yet unless you buy a Dell. There are portable drives that use PR as well, but currently Seagate is the only company selling standard ATA/SCSI drives using PR.

it is not like hitachi wont sell to the general public here in a bit....so who cares if you can't get one yet.

the thing with the 15k.5 is that it is the only 15k hdd you can get that is 300GB in size, i think that is the niche they are filling - even if it doesn't beat all the other 15k drives, it does the 10K, so if you want/need 15k and 300GB you have no choice - think of datacenters...but then again, they are probably all going the 10-15K 2.5 sas drives..

 

[bob4432]

Originally posted by: ryan256

Originally posted by: Pariah

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau,

And all of those drives are SCSI and run into some serious money. Maybe I should have been a little more clear in the OP. This is for a personal data, file, web, ftp server. NOT an enterprise production environment. At most there will be 5 people using this server not 500. I was mainly wanting to find out if there would be any real difference in these 2 Seagate drives when put into RAID5 configuration.

again, to quote myself:

it has shown in different benches (search the storage portion of anandtech) that ncq doesn't do much for sata stuff. basically you are comparing a 7200.9 drive to a 7200.10 drive. the 7200.10 drives did have really good str rates, but that was about it. if i were you, i would search around for some 7200.9 vs 7200.10 benches and see if it is worth it. i would say that for 3 drives it is not worth $75 if that is the only difference, but i remember people not liking the 7200.9 drives for some other reason - search and find out why...sorry i can't remember

 

[Zepper]

The Seagate 15k5 does beat all others in raw transfer rate at near 125MB/sec on the outer cylinders and over 100MB/s average. It may well miss on other scenarios like a server test suite. The fact that you'd have to buy two of any other SCSI drive to match its capacity doesn't hurt it either.

.bh.

 

[bob4432]

Originally posted by: Zepper
The Seagate 15k5 does beat all others in raw transfer rate at near 125MB/sec on the outer cylinders and over 100MB/s average. It may well miss on other scenarios like a server test suite. The fact that you'd have to buy two of any other SCSI drive to match its capacity doesn't hurt it either.

.bh.

agreed - on my choked up pci bus i get 96MB/s burst and 96MB/s avg...hahaha and the lowest it goes it ~80+MB/s

 

[Pariah]

Originally posted by: ryan256

Originally posted by: Pariah

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau,

And all of those drives are SCSI and run into some serious money. Maybe I should have been a little more clear in the OP. This is for a personal data, file, web, ftp server. NOT an enterprise production environment. At most there will be 5 people using this server not 500. I was mainly wanting to find out if there would be any real difference in these 2 Seagate drives when put into RAID5 configuration.

Ignoring everything else, the main point is if performance is actually an issue, you should not be looking at Seagate. If you still insist on getting one of those 2 drives, then get the ST3500630AS, for the simple reason that it is a newer drive (7200.10 vs 7200.9), since newer drives typically perform better than older ones... duh. Though, I certainly don't think the 7200.10 is worth $25 more than the 7200.9.

it is not like hitachi wont sell to the general public here in a bit....so who cares if you can't get one yet.

When the discussion is who sells drives with PR, whether or not you can get one would seem to carry some relevance...

agreed - on my choked up pci bus i get 96MB/s burst and 96MB/s avg...hahaha and the lowest it goes it ~80+MB/s

I think it's about time to upgrade that original slot A Athlon VIA chipset motherboard you're using.

 

[bob4432]

Originally posted by: Pariah

Originally posted by: ryan256

Originally posted by: Pariah

Originally posted by: Rubycon
The 15k.5 is not a desktop drive.

No, it isn't, but neither are the Maxtor Atlas 15k II or Fujitsu Mau,

And all of those drives are SCSI and run into some serious money. Maybe I should have been a little more clear in the OP. This is for a personal data, file, web, ftp server. NOT an enterprise production environment. At most there will be 5 people using this server not 500. I was mainly wanting to find out if there would be any real difference in these 2 Seagate drives when put into RAID5 configuration.

Ignoring everything else, the main point is if performance is actually an issue, you should not be looking at Seagate. If you still insist on getting one of those 2 drives, then get the ST3500630AS, for the simple reason that it is a newer drive (7200.10 vs 7200.9), since newer drives typically perform better than older ones... duh. Though, I certainly don't think the 7200.10 is worth $25 more than the 7200.9.

it is not like hitachi wont sell to the general public here in a bit....so who cares if you can't get one yet.

When the discussion is who sells drives with PR, whether or not you can get one would seem to carry some relevance...

agreed - on my choked up pci bus i get 96MB/s burst and 96MB/s avg...hahaha and the lowest it goes it ~80+MB/s

I think it's about time to upgrade that original slot A Athlon VIA chipset motherboard you're using.

the hitachi 1TB drives will be available soon. why they are not available atm is kind of a dumb idea i agree, but i have heard 2-3wks, which is just a small price to pay for that amount of storeage, and besides, you can get one currently under certain circumstances

as far as the pci bus - considering i am running 2 pata hdds, 2 optical hdds and all the pci slots are filled, i feel 96MB/s isn't too bad when theoretical max for the entire bus is 133MB/s