Thread: Intel SRCS16 SATA raid?
Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller instead of the 3ware one. Poking around it seems this does come with Linux drivers and there is a battery backup option. So it doesn't seem to be completely insane. Anyone have any experience with these controllers? I'm also wondering about whether I'm better off with one of these SATA raid controllers or just going with SCSI drives. -- greg
sorry, don't remember whether it's SCSI or SATA II, but IIRC the Areca controllers are just stellar for things. If you do get SATA for db stuff..especially multiuser...i still haven't seen anything to indicate an across-the-board primacy for SATA over SCSI. I'd go w/SCSI, or if SATA for $$$ reasons, I'd be sure to have many spindles and RAID 10. my 0.02. I'm surely not an expert of any kind. -----Original Message----- From: pgsql-performance-owner@postgresql.org [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Greg Stark Sent: Thursday, April 14, 2005 10:55 AM To: pgsql-performance@postgresql.org Subject: [PERFORM] Intel SRCS16 SATA raid? Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller instead of the 3ware one. Poking around it seems this does come with Linux drivers and there is a battery backup option. So it doesn't seem to be completelyinsane. Anyone have any experience with these controllers? I'm also wondering about whether I'm better off with one of these SATA raid controllers or just going with SCSI drives. -- greg ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
Greg, I posted this link under a different thread (the $7k server thread). It is a very good read on why SCSI is better for servers than ATA. I didn't note bias, though it is from a drive manufacturer. YMMV. There is an interesting, though dated appendix on different manufacturers' drive characteristics. http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf Enjoy, Rick pgsql-performance-owner@postgresql.org wrote on 04/14/2005 09:54:45 AM: > > Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller > instead of the 3ware one. > > Poking around it seems this does come with Linux drivers and there is a > battery backup option. So it doesn't seem to be completely insane. > > Anyone have any experience with these controllers? > > I'm also wondering about whether I'm better off with one of these SATA raid > controllers or just going with SCSI drives. > > -- > greg > > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend
I have read a large chunk of this, and I would highly recommend it to anyone who has been participating in the drive discussions. It is most informative!! Alex Turner netEconomist On 4/14/05, Richard_D_Levine@raytheon.com <Richard_D_Levine@raytheon.com> wrote: > Greg, > > I posted this link under a different thread (the $7k server thread). It is > a very good read on why SCSI is better for servers than ATA. I didn't note > bias, though it is from a drive manufacturer. YMMV. There is an > interesting, though dated appendix on different manufacturers' drive > characteristics. > > http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf > > Enjoy, > > Rick > > pgsql-performance-owner@postgresql.org wrote on 04/14/2005 09:54:45 AM: > > > > > Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller > > instead of the 3ware one. > > > > Poking around it seems this does come with Linux drivers and there is a > > battery backup option. So it doesn't seem to be completely insane. > > > > Anyone have any experience with these controllers? > > > > I'm also wondering about whether I'm better off with one of these SATA > raid > > controllers or just going with SCSI drives. > > > > -- > > greg > > > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 8: explain analyze is your friend > > ---------------------------(end of broadcast)--------------------------- > TIP 9: the planner will ignore your desire to choose an index scan if your > joining column's datatypes do not match >
I have put together a little head to head performance of a 15k SCSI, 10k SCSI 10K SATA w/TCQ, 10K SATA wo/TCQ and 7.2K SATA drive comparison at storage review http://www.storagereview.com/php/benchmark/compare_rtg_2001.php?typeID=10&testbedID=3&osID=4&raidconfigID=1&numDrives=1&devID_0=232&devID_1=40&devID_2=259&devID_3=267&devID_4=261&devID_5=248&devCnt=6 It does illustrate some of the weaknesses of SATA drives, but all in all the Raptor drives put on a good show. Alex Turner netEconomist On 4/14/05, Alex Turner <armtuk@gmail.com> wrote: > I have read a large chunk of this, and I would highly recommend it to > anyone who has been participating in the drive discussions. It is > most informative!! > > Alex Turner > netEconomist > > On 4/14/05, Richard_D_Levine@raytheon.com <Richard_D_Levine@raytheon.com> wrote: > > Greg, > > > > I posted this link under a different thread (the $7k server thread). It is > > a very good read on why SCSI is better for servers than ATA. I didn't note > > bias, though it is from a drive manufacturer. YMMV. There is an > > interesting, though dated appendix on different manufacturers' drive > > characteristics. > > > > http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf > > > > Enjoy, > > > > Rick > > > > pgsql-performance-owner@postgresql.org wrote on 04/14/2005 09:54:45 AM: > > > > > > > > Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller > > > instead of the 3ware one. > > > > > > Poking around it seems this does come with Linux drivers and there is a > > > battery backup option. So it doesn't seem to be completely insane. > > > > > > Anyone have any experience with these controllers? > > > > > > I'm also wondering about whether I'm better off with one of these SATA > > raid > > > controllers or just going with SCSI drives. > > > > > > -- > > > greg > > > > > > > > > ---------------------------(end of broadcast)--------------------------- > > > TIP 8: explain analyze is your friend > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 9: the planner will ignore your desire to choose an index scan if your > > joining column's datatypes do not match > > >
> -----Original Message----- > From: Alex Turner [mailto:armtuk@gmail.com] > Sent: Thursday, April 14, 2005 12:14 PM > To: Richard_D_Levine@raytheon.com > Cc: Greg Stark; pgsql-performance@postgresql.org; > pgsql-performance-owner@postgresql.org > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > I have put together a little head to head performance of a 15k SCSI, > 10k SCSI 10K SATA w/TCQ, 10K SATA wo/TCQ and 7.2K SATA drive > comparison at storage review > > http://www.storagereview.com/php/benchmark/compare_rtg_2001.ph > p?typeID=10&testbedID=3&osID=4&raidconfigID=1&numDrives=1&devI > D_0=232&devID_1=40&devID_2=259&devID_3=267&devID_4=261&devID_5 > =248&devCnt=6 > > It does illustrate some of the weaknesses of SATA drives, but all in > all the Raptor drives put on a good show. > [...] I think it's a little misleading that your tests show 0ms seek times for some of the write tests. The environmental test also selects a missing data point as the winner. Besides that, it seems to me that seek time is one of the most important features for a DB server, which means that the SCSI drives are the clear winners and the non-WD SATA drives are the embarrassing losers. Transfer rate is import, but perhaps less so because DBs tend to read/write small blocks rather than large files. On the server suite, which seems to me to be the most relevant for DBs, the Atlas 15k spanks the other drives by a fairly large margin (especially the lesser SATA drives). When you ignore the "consumer app" benchmarks, I wouldn't be so confident in saying that the Raptors "put on a good show". __ David B. Held Software Engineer/Array Services Group 200 14th Ave. East, Sartell, MN 56377 320.534.3637 320.253.7800 800.752.8129
Nice research Alex. Your data strongly support the information in the paper. Your SCSI drives blew away the others in all of the server benchmarks. They're only marginally better in desktop use. I do find it somewhat amazing that a 15K SCSI 320 drive isn't going to help me play Unreal Tournament much faster. That's okay. I suck at it anyway. My kid has never lost to me. She enjoys seeing daddy as a bloody smear and bouncing body parts anyway. It promotes togetherness. Here's a quote from the paper: "[SCSI] interfaces support multiple initiators or hosts. The drive must keep track of separate sets of information for each host to which it is attached, e.g., maintaining the processor pointer sets for multiple initiators and tagged commands. The capability of SCSI/FC to efficiently process commands and tasks in parallel has also resulted in a higher overhead “kernel” structure for the firmware." Has anyone ever seen a system with multiple hosts or initiators on a SCSI bus? Seems like it would be a very cool thing in an SMP architecture, but I've not seen an example implemented. Rick Alex Turner <armtuk@gmail.com> wrote on 04/14/2005 12:13:41 PM: > I have put together a little head to head performance of a 15k SCSI, > 10k SCSI 10K SATA w/TCQ, 10K SATA wo/TCQ and 7.2K SATA drive > comparison at storage review > > http://www.storagereview.com/php/benchmark/compare_rtg_2001.php? > typeID=10&testbedID=3&osID=4&raidconfigID=1&numDrives=1&devID_0=232&devID_1=40&devID_2=259&devID_3=267&devID_4=261&devID_5=248&devCnt=6 > > It does illustrate some of the weaknesses of SATA drives, but all in > all the Raptor drives put on a good show. > > Alex Turner > netEconomist > > On 4/14/05, Alex Turner <armtuk@gmail.com> wrote: > > I have read a large chunk of this, and I would highly recommend it to > > anyone who has been participating in the drive discussions. It is > > most informative!! > > > > Alex Turner > > netEconomist > > > > On 4/14/05, Richard_D_Levine@raytheon.com > <Richard_D_Levine@raytheon.com> wrote: > > > Greg, > > > > > > I posted this link under a different thread (the $7k server > thread). It is > > > a very good read on why SCSI is better for servers than ATA. I > didn't note > > > bias, though it is from a drive manufacturer. YMMV. There is an > > > interesting, though dated appendix on different manufacturers' drive > > > characteristics. > > > > > > http://www.seagate. > com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf > > > > > > Enjoy, > > > > > > Rick > > > > > > pgsql-performance-owner@postgresql.org wrote on 04/14/2005 09:54:45 AM: > > > > > > > > > > > Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller > > > > instead of the 3ware one. > > > > > > > > Poking around it seems this does come with Linux drivers and there is a > > > > battery backup option. So it doesn't seem to be completely insane. > > > > > > > > Anyone have any experience with these controllers? > > > > > > > > I'm also wondering about whether I'm better off with one of these SATA > > > raid > > > > controllers or just going with SCSI drives. > > > > > > > > -- > > > > greg > > > > > > > > > > > > ---------------------------(end of broadcast)--------------------------- > > > > TIP 8: explain analyze is your friend > > > > > > ---------------------------(end of broadcast)--------------------------- > > > TIP 9: the planner will ignore your desire to choose an index scan if your > > > joining column's datatypes do not match > > > > >
> > >Our vendor is trying to sell us on an Intel SRCS16 SATA raid controller instead of the 3ware one. > > Well I have never even heard of it. 3ware is the defacto authority of reasonable SATA RAID. If you were to go with a different brand I would go with LSI. The LSI 150-6 is a nice card with a battery backup option as well. Oh and 3ware has BBU for certain models as well. Sincerely, Joshua D. Drake
Just to clarify these are tests from http://www.storagereview.com, not my own. I guess they couldn't get number for those parts. I think everyone understands that a 0ms seek time impossible, and indicates a missing data point. Thanks, Alex Turner netEconomist On 4/14/05, Dave Held <dave.held@arrayservicesgrp.com> wrote: > > -----Original Message----- > > From: Alex Turner [mailto:armtuk@gmail.com] > > Sent: Thursday, April 14, 2005 12:14 PM > > To: Richard_D_Levine@raytheon.com > > Cc: Greg Stark; pgsql-performance@postgresql.org; > > pgsql-performance-owner@postgresql.org > > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > > > > I have put together a little head to head performance of a 15k SCSI, > > 10k SCSI 10K SATA w/TCQ, 10K SATA wo/TCQ and 7.2K SATA drive > > comparison at storage review > > > > http://www.storagereview.com/php/benchmark/compare_rtg_2001.ph > > p?typeID=10&testbedID=3&osID=4&raidconfigID=1&numDrives=1&devI > > D_0=232&devID_1=40&devID_2=259&devID_3=267&devID_4=261&devID_5 > > =248&devCnt=6 > > > > It does illustrate some of the weaknesses of SATA drives, but all in > > all the Raptor drives put on a good show. > > [...] > > I think it's a little misleading that your tests show 0ms seek times > for some of the write tests. The environmental test also selects a > missing data point as the winner. Besides that, it seems to me that > seek time is one of the most important features for a DB server, which > means that the SCSI drives are the clear winners and the non-WD SATA > drives are the embarrassing losers. Transfer rate is import, but > perhaps less so because DBs tend to read/write small blocks rather > than large files. On the server suite, which seems to me to be the > most relevant for DBs, the Atlas 15k spanks the other drives by a > fairly large margin (especially the lesser SATA drives). When you > ignore the "consumer app" benchmarks, I wouldn't be so confident in > saying that the Raptors "put on a good show". > > __ > David B. Held > Software Engineer/Array Services Group > 200 14th Ave. East, Sartell, MN 56377 > 320.534.3637 320.253.7800 800.752.8129 > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend >
Looking at the numbers, the raptor with TCQ enabled was close or beat the Atlas III 10k drive on most benchmarks. Naturaly a 15k drive is going to be faster in many areas, but it is also much more expensive. It was only 44% better on the server tests than the raptor with TCQ, but it costs nearly 300% more ($538 cdw.com, $180 newegg.com). Note also that the 15k drive was the only drive that kept up with the raptor on raw transfer speed, which is going to matter for WAL. For those of us on a budget, a quality controller card with lots of RAM is going to be our biggest friend because it can cache writes, and improve performance. The 3ware controllers seem to be universally benchmarked as the best SATA RAID 10 controllers where database performance is concerned. Even the crappy tweakers.net review had the 3ware as the fastest controller for a MySQL data partition in RAID 10. The Raptor drives can be had for as little as $180/ea, which is quite a good price point considering they can keep up with their SCSI 10k RPM counterparts on almost all tests with NCQ enabled (Note that 3ware controllers _don't_ support NCQ, although they claim their HBA based queueing is 95% as good as NCQ on the drive). Alex Turner netEconomist On 4/14/05, Dave Held <dave.held@arrayservicesgrp.com> wrote: > > -----Original Message----- > > From: Alex Turner [mailto:armtuk@gmail.com] > > Sent: Thursday, April 14, 2005 12:14 PM > > To: Richard_D_Levine@raytheon.com > > Cc: Greg Stark; pgsql-performance@postgresql.org; > > pgsql-performance-owner@postgresql.org > > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > > > > I have put together a little head to head performance of a 15k SCSI, > > 10k SCSI 10K SATA w/TCQ, 10K SATA wo/TCQ and 7.2K SATA drive > > comparison at storage review > > > > http://www.storagereview.com/php/benchmark/compare_rtg_2001.ph > > p?typeID=10&testbedID=3&osID=4&raidconfigID=1&numDrives=1&devI > > D_0=232&devID_1=40&devID_2=259&devID_3=267&devID_4=261&devID_5 > > =248&devCnt=6 > > > > It does illustrate some of the weaknesses of SATA drives, but all in > > all the Raptor drives put on a good show. > > [...] > > I think it's a little misleading that your tests show 0ms seek times > for some of the write tests. The environmental test also selects a > missing data point as the winner. Besides that, it seems to me that > seek time is one of the most important features for a DB server, which > means that the SCSI drives are the clear winners and the non-WD SATA > drives are the embarrassing losers. Transfer rate is import, but > perhaps less so because DBs tend to read/write small blocks rather > than large files. On the server suite, which seems to me to be the > most relevant for DBs, the Atlas 15k spanks the other drives by a > fairly large margin (especially the lesser SATA drives). When you > ignore the "consumer app" benchmarks, I wouldn't be so confident in > saying that the Raptors "put on a good show". > > __ > David B. Held > Software Engineer/Array Services Group > 200 14th Ave. East, Sartell, MN 56377 > 320.534.3637 320.253.7800 800.752.8129 > > ---------------------------(end of broadcast)--------------------------- > TIP 8: explain analyze is your friend >
Alex Turner wrote: > Looking at the numbers, the raptor with TCQ enabled was close or beat > the Atlas III 10k drive on most benchmarks. > > Naturaly a 15k drive is going to be faster in many areas, but it is > also much more expensive. It was only 44% better on the server tests > than the raptor with TCQ, but it costs nearly 300% more ($538 cdw.com, > $180 newegg.com). True, but that's a one time expense (300%) for a 44% gain ALL the time. '44% better' is nothing to sneeze at. I'd easily pay the price for the gain in a large server env. -- Until later, Geoffrey
Joshua D. Drake wrote: > Well I have never even heard of it. 3ware is the defacto authority of > reasonable SATA RAID. no! 3ware was rather early in this business, but there are plenty of (IMHO, and some other people's opinion) better alternatives available. 3ware has good Linux drivers, but the performance of their current controllers isn't that good. Have a look at this: http://www.tweakers.net/reviews/557/1 especially the sequential writes with RAID-5 on this page: http://www.tweakers.net/reviews/557/19 We have been a long-time user of a 3ware 8506 controller (8 disks, RAID-5) and have purchased 2 Areca ARC-1120 now since we weren't satisfied with the performance and the 2TB per array limit... -mjy
> -----Original Message----- > From: Alex Turner [mailto:armtuk@gmail.com] > Sent: Thursday, April 14, 2005 6:15 PM > To: Dave Held > Cc: pgsql-performance@postgresql.org > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > Looking at the numbers, the raptor with TCQ enabled was close or > beat the Atlas III 10k drive on most benchmarks. And I would be willing to bet that the Atlas 10k is not using the same generation of technology as the Raptors. > Naturaly a 15k drive is going to be faster in many areas, but it > is also much more expensive. It was only 44% better on the server > tests than the raptor with TCQ, but it costs nearly 300% more ($538 > cdw.com, $180 newegg.com). State that in terms of cars. Would you be willing to pay 300% more for a car that is 44% faster than your competitor's? Of course you would, because we all recognize that the cost of speed/performance does not scale linearly. Naturally, you buy the best speed that you can afford, but when it comes to hard drives, the only major feature whose price tends to scale anywhere close to linearly is capacity. > Note also that the 15k drive was the only drive that kept up with > the raptor on raw transfer speed, which is going to matter for WAL. So get a Raptor for your WAL partition. ;) > [...] > The Raptor drives can be had for as little as $180/ea, which is > quite a good price point considering they can keep up with their > SCSI 10k RPM counterparts on almost all tests with NCQ enabled > (Note that 3ware controllers _don't_ support NCQ, although they > claim their HBA based queueing is 95% as good as NCQ on the drive). Just keep in mind the points made by the Seagate article. You're buying much more than just performance for that $500+. You're also buying vibrational tolerance, high MTBF, better internal environmental controls, and a pretty significant margin on seek time, which is probably your most important feature for disks storing tables. An interesting test would be to stick several drives in a cabinet and graph how performance is affected at the different price points/ technologies/number of drives. __ David B. Held Software Engineer/Array Services Group 200 14th Ave. East, Sartell, MN 56377 320.534.3637 320.253.7800 800.752.8129
Dave wrote "An interesting test would be to stick several drives in a cabinet and graph how performance is affected at the different price points/ technologies/number of drives." From the discussion on the $7k server thread, it seems the RAID controller would be an important data point also. And RAID level. And application load/kind. Hmmm. I just talked myself out of it. Seems like I'd end up with something akin to those database benchmarks we all love to hate. Rick pgsql-performance-owner@postgresql.org wrote on 04/15/2005 08:40:13 AM: > > -----Original Message----- > > From: Alex Turner [mailto:armtuk@gmail.com] > > Sent: Thursday, April 14, 2005 6:15 PM > > To: Dave Held > > Cc: pgsql-performance@postgresql.org > > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > > Looking at the numbers, the raptor with TCQ enabled was close or > > beat the Atlas III 10k drive on most benchmarks. > > And I would be willing to bet that the Atlas 10k is not using the > same generation of technology as the Raptors. > > > Naturaly a 15k drive is going to be faster in many areas, but it > > is also much more expensive. It was only 44% better on the server > > tests than the raptor with TCQ, but it costs nearly 300% more ($538 > > cdw.com, $180 newegg.com). > > State that in terms of cars. Would you be willing to pay 300% more > for a car that is 44% faster than your competitor's? Of course you > would, because we all recognize that the cost of speed/performance > does not scale linearly. Naturally, you buy the best speed that you > can afford, but when it comes to hard drives, the only major feature > whose price tends to scale anywhere close to linearly is capacity. > > > Note also that the 15k drive was the only drive that kept up with > > the raptor on raw transfer speed, which is going to matter for WAL. > > So get a Raptor for your WAL partition. ;) > > > [...] > > The Raptor drives can be had for as little as $180/ea, which is > > quite a good price point considering they can keep up with their > > SCSI 10k RPM counterparts on almost all tests with NCQ enabled > > (Note that 3ware controllers _don't_ support NCQ, although they > > claim their HBA based queueing is 95% as good as NCQ on the drive). > > Just keep in mind the points made by the Seagate article. You're > buying much more than just performance for that $500+. You're also > buying vibrational tolerance, high MTBF, better internal > environmental controls, and a pretty significant margin on seek time, > which is probably your most important feature for disks storing tables. > An interesting test would be to stick several drives in a cabinet and > graph how performance is affected at the different price points/ > technologies/number of drives. > > __ > David B. Held > Software Engineer/Array Services Group > 200 14th Ave. East, Sartell, MN 56377 > 320.534.3637 320.253.7800 800.752.8129 > > ---------------------------(end of broadcast)--------------------------- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly
No offense to that review, but it was really wasn't that good, and drew bad conclusions from the data. I posted it originaly and immediately regretted it. See http://www.tweakers.net/reviews/557/18 Amazingly the controller with 1Gig cache manages a write throughput of 750MB/sec on a single drive. quote: "Floating high above the crowd, the ARC-1120 has a perfect view on the struggles of the other adapters. " It's because the adapter has 1Gig of RAM, nothing to do with the RAID architecture, it's clearly caching the entire dataset. The drive can't physicaly run that fast. These guys really don't know what they are doing. Curiously: http://www.tweakers.net/reviews/557/25 The 3ware does very well as a data drive for MySQL. The size of your cache is going to _directly_ affect RAID 5 performance. Put a gig of memory in a 3ware 9500S and benchmark it against the Areca then. Also - folks don't run data paritions on RAID 5 because the write speed is too low. When you look at the results for RAID 10, the 3ware leads the pack. See also: http://www20.tomshardware.com/storage/20041227/areca-raid6-06.html I trust toms hardware a little more to set up a good review to be honest. The 3ware trounces the Areca in all IO/sec test. Alex Turner netEconomist On 4/15/05, Marinos Yannikos <mjy@geizhals.at> wrote: > Joshua D. Drake wrote: > > Well I have never even heard of it. 3ware is the defacto authority of > > reasonable SATA RAID. > > no! 3ware was rather early in this business, but there are plenty of > (IMHO, and some other people's opinion) better alternatives available. > 3ware has good Linux drivers, but the performance of their current > controllers isn't that good. > > Have a look at this: http://www.tweakers.net/reviews/557/1 > > especially the sequential writes with RAID-5 on this page: > > http://www.tweakers.net/reviews/557/19 > > We have been a long-time user of a 3ware 8506 controller (8 disks, > RAID-5) and have purchased 2 Areca ARC-1120 now since we weren't > satisfied with the performance and the 2TB per array limit... > > -mjy > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster >
The original thread was how much can I get for $7k You can't fit a 15k RPM SCSI solution into $7K ;) Some of us are on a budget! 10k RPM SATA drives give acceptable performance at a good price, thats really the point here. I have never really argued that SATA is going to match SCSI performance on multidrive arrays for IO/sec. But it's all about the benjamins baby. If I told my boss we need $25k for a database machine, he'd tell me that was impossible, and I have $5k to do it. If I tell him $7k - he will swallow that. We don't _need_ the amazing performance of a 15k RPM drive config. Our biggest hit is reads, so we can buy 3xSATA machines and load balance. It's all about the application, and buying what is appropriate. I don't buy a Corvette if all I need is a malibu. Alex Turner netEconomist On 4/15/05, Dave Held <dave.held@arrayservicesgrp.com> wrote: > > -----Original Message----- > > From: Alex Turner [mailto:armtuk@gmail.com] > > Sent: Thursday, April 14, 2005 6:15 PM > > To: Dave Held > > Cc: pgsql-performance@postgresql.org > > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > > Looking at the numbers, the raptor with TCQ enabled was close or > > beat the Atlas III 10k drive on most benchmarks. > > And I would be willing to bet that the Atlas 10k is not using the > same generation of technology as the Raptors. > > > Naturaly a 15k drive is going to be faster in many areas, but it > > is also much more expensive. It was only 44% better on the server > > tests than the raptor with TCQ, but it costs nearly 300% more ($538 > > cdw.com, $180 newegg.com). > > State that in terms of cars. Would you be willing to pay 300% more > for a car that is 44% faster than your competitor's? Of course you > would, because we all recognize that the cost of speed/performance > does not scale linearly. Naturally, you buy the best speed that you > can afford, but when it comes to hard drives, the only major feature > whose price tends to scale anywhere close to linearly is capacity. > > > Note also that the 15k drive was the only drive that kept up with > > the raptor on raw transfer speed, which is going to matter for WAL. > > So get a Raptor for your WAL partition. ;) > > > [...] > > The Raptor drives can be had for as little as $180/ea, which is > > quite a good price point considering they can keep up with their > > SCSI 10k RPM counterparts on almost all tests with NCQ enabled > > (Note that 3ware controllers _don't_ support NCQ, although they > > claim their HBA based queueing is 95% as good as NCQ on the drive). > > Just keep in mind the points made by the Seagate article. You're > buying much more than just performance for that $500+. You're also > buying vibrational tolerance, high MTBF, better internal > environmental controls, and a pretty significant margin on seek time, > which is probably your most important feature for disks storing tables. > An interesting test would be to stick several drives in a cabinet and > graph how performance is affected at the different price points/ > technologies/number of drives. > > __ > David B. Held > Software Engineer/Array Services Group > 200 14th Ave. East, Sartell, MN 56377 > 320.534.3637 320.253.7800 800.752.8129 > > ---------------------------(end of broadcast)--------------------------- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly >
> -----Original Message----- > From: Alex Turner [mailto:armtuk@gmail.com] > Sent: Friday, April 15, 2005 9:44 AM > To: Marinos Yannikos > Cc: Joshua D. Drake; Mohan, Ross; pgsql-performance@postgresql.org > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > No offense to that review, but it was really wasn't that good, > and drew bad conclusions from the data. I posted it originaly > and immediately regretted it. I didn't read the whole thing, but it didn't seem that bad to me. > See http://www.tweakers.net/reviews/557/18 > > Amazingly the controller with 1Gig cache manages a write throughput > of 750MB/sec on a single drive. > > quote: > "Floating high above the crowd, the ARC-1120 has a perfect view on > the struggles of the other adapters. " > > It's because the adapter has 1Gig of RAM, nothing to do with the RAID > architecture, it's clearly caching the entire dataset. The drive > can't physicaly run that fast. And that's pretty much exactly what the article says. Even before the part you quoted. Not sure what the problem is there. > These guys really don't know what they are doing. They weren't pretending that the drive array was serving up data at that rate directly from the physical media. They clearly indicated that they were testing controller cache speed with the small test. > Curiously: > http://www.tweakers.net/reviews/557/25 > > The 3ware does very well as a data drive for MySQL. > [...] If you take a close look, they pretty much outright say that the Areca controller does very poorly on the random accesses typical of DB work. They also specifically mention that the 3ware still dominates the competition in this area. Dave __ David B. Held Software Engineer/Array Services Group 200 14th Ave. East, Sartell, MN 56377 320.534.3637 320.253.7800 800.752.8129
This is a different thread that the $7k server thread. Greg Stark started it and wrote: "I'm also wondering about whether I'm better off with one of these SATA raid controllers or just going with SCSI drives." Rick pgsql-performance-owner@postgresql.org wrote on 04/15/2005 10:01:56 AM: > The original thread was how much can I get for $7k > > You can't fit a 15k RPM SCSI solution into $7K ;) Some of us are ona budget! > > 10k RPM SATA drives give acceptable performance at a good price, thats > really the point here. > > I have never really argued that SATA is going to match SCSI > performance on multidrive arrays for IO/sec. But it's all about the > benjamins baby. If I told my boss we need $25k for a database > machine, he'd tell me that was impossible, and I have $5k to do it. > If I tell him $7k - he will swallow that. We don't _need_ the amazing > performance of a 15k RPM drive config. Our biggest hit is reads, so > we can buy 3xSATA machines and load balance. It's all about the > application, and buying what is appropriate. I don't buy a Corvette > if all I need is a malibu. > > Alex Turner > netEconomist > > On 4/15/05, Dave Held <dave.held@arrayservicesgrp.com> wrote: > > > -----Original Message----- > > > From: Alex Turner [mailto:armtuk@gmail.com] > > > Sent: Thursday, April 14, 2005 6:15 PM > > > To: Dave Held > > > Cc: pgsql-performance@postgresql.org > > > Subject: Re: [PERFORM] Intel SRCS16 SATA raid? > > > > > > Looking at the numbers, the raptor with TCQ enabled was close or > > > beat the Atlas III 10k drive on most benchmarks. > > > > And I would be willing to bet that the Atlas 10k is not using the > > same generation of technology as the Raptors. > > > > > Naturaly a 15k drive is going to be faster in many areas, but it > > > is also much more expensive. It was only 44% better on the server > > > tests than the raptor with TCQ, but it costs nearly 300% more ($538 > > > cdw.com, $180 newegg.com). > > > > State that in terms of cars. Would you be willing to pay 300% more > > for a car that is 44% faster than your competitor's? Of course you > > would, because we all recognize that the cost of speed/performance > > does not scale linearly. Naturally, you buy the best speed that you > > can afford, but when it comes to hard drives, the only major feature > > whose price tends to scale anywhere close to linearly is capacity. > > > > > Note also that the 15k drive was the only drive that kept up with > > > the raptor on raw transfer speed, which is going to matter for WAL. > > > > So get a Raptor for your WAL partition. ;) > > > > > [...] > > > The Raptor drives can be had for as little as $180/ea, which is > > > quite a good price point considering they can keep up with their > > > SCSI 10k RPM counterparts on almost all tests with NCQ enabled > > > (Note that 3ware controllers _don't_ support NCQ, although they > > > claim their HBA based queueing is 95% as good as NCQ on the drive). > > > > Just keep in mind the points made by the Seagate article. You're > > buying much more than just performance for that $500+. You're also > > buying vibrational tolerance, high MTBF, better internal > > environmental controls, and a pretty significant margin on seek time, > > which is probably your most important feature for disks storing tables. > > An interesting test would be to stick several drives in a cabinet and > > graph how performance is affected at the different price points/ > > technologies/number of drives. > > > > __ > > David B. Held > > Software Engineer/Array Services Group > > 200 14th Ave. East, Sartell, MN 56377 > > 320.534.3637 320.253.7800 800.752.8129 > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 3: if posting/reading through Usenet, please send an appropriate > > subscribe-nomail command to majordomo@postgresql.org so that your > > message can get through to the mailing list cleanly > > > > ---------------------------(end of broadcast)--------------------------- > TIP 7: don't forget to increase your free space map settings
On Apr 15, 2005, at 11:01 AM, Alex Turner wrote: > You can't fit a 15k RPM SCSI solution into $7K ;) Some of us are on a > budget! > I just bought a pair of Dual Opteron, 4GB RAM, LSI 320-2X RAID dual channel with 8 36GB 15kRPM seagate drives. Each one of these boxes set me back just over $7k, including onsite warrantee. They totally blow away the Dell Dual XEON with external 14 disk RAID (also 15kRPM drives, manufacturer unknown) which also has 4GB RAM and a Dell PERC 3/DC controller, the whole of which set me back over $15k. Vivek Khera, Ph.D. +1-301-869-4449 x806
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I stand corrected! Maybe I should re-evaluate our own config! Alex T (The dell PERC controllers do pretty much suck on linux) On 4/15/05, Vivek Khera <vivek@khera.org> wrote: > > On Apr 15, 2005, at 11:01 AM, Alex Turner wrote: > > > You can't fit a 15k RPM SCSI solution into $7K ;) Some of us are on a > > budget! > > > > I just bought a pair of Dual Opteron, 4GB RAM, LSI 320-2X RAID dual > channel with 8 36GB 15kRPM seagate drives. Each one of these boxes set > me back just over $7k, including onsite warrantee. > > They totally blow away the Dell Dual XEON with external 14 disk RAID > (also 15kRPM drives, manufacturer unknown) which also has 4GB RAM and a > Dell PERC 3/DC controller, the whole of which set me back over $15k. > > Vivek Khera, Ph.D. > +1-301-869-4449 x806 > > >
Alex Turner wrote: > No offense to that review, but it was really wasn't that good, and > drew bad conclusions from the data. I posted it originaly and > immediately regretted it. > > See http://www.tweakers.net/reviews/557/18 > > Amazingly the controller with 1Gig cache manages a write throughput of > 750MB/sec on a single drive. > > quote: > "Floating high above the crowd, the ARC-1120 has a perfect view on the > struggles of the other adapters. " > > It's because the adapter has 1Gig of RAM, nothing to do with the RAID > architecture, it's clearly caching the entire dataset. The drive > can't physicaly run that fast. These guys really don't know what they > are doing. Perhaps you didn't read the whole page. It says right at the beginning: "Because of its simplicity and short test duration, the ATTO Disk Benchmark is used a lot for comparing the 'peformance' of hard disks. The tool measures the sequential transfer rate of a partition using a test length of 32MB at most. Because of this small dataset, ATTO is unsuitable for measuring media transfer rates of intelligent RAID-adapters which are equipped with cache memory. The smart RAID adapters will serve the requested data directly from their cache, as a result of which the results have no relationship to the media transfer rates of these cards. For this reason ATTO is an ideal tool to test the cache transfer rates of intelligent RAID-adapters." Therefore, the results on this page are valid - they're supposed to show the cache/transfer speed, the dataset is 32MB(!) and should fit in the caches of all cards. > See also: > http://www20.tomshardware.com/storage/20041227/areca-raid6-06.html > > I trust toms hardware a little more to set up a good review to be honest. I don't, for many (historical) reasons. > The 3ware trounces the Areca in all IO/sec test. Maybe, but with no mention of stripe size and other configuration details, this is somewhat suspicious. I'll be able to offer benchmarks for the 8506-8 vs. the 1120 shortly (1-2 weeks), if you're interested (pg_bench, for example, to be a bit more on-topic). Regards, Marinos
Richard_D_Levine@raytheon.com wrote: > Greg, > > I posted this link under a different thread (the $7k server thread). It is > a very good read on why SCSI is better for servers than ATA. I didn't note > bias, though it is from a drive manufacturer. YMMV. There is an > interesting, though dated appendix on different manufacturers' drive > characteristics. > > http://www.seagate.com/content/docs/pdf/whitepaper/D2c_More_than_Interface_ATA_vs_SCSI_042003.pdf I have read this and it is an _excellent_ read about disk drives. The bottom line is that the SCSI/IDE distinctions is more of an indicator of the drive, rather than the main feature of the drive. The main feature is that certain drives are Enterprise Storage and are designed for high reliability and speed, while Personal Server drives are designed for low cost. The IDE/SCSI issue is only an indicator of this. There are a lot more variabilities between these two types of drives than I knew. I recommend it for anyone who is choosing drives for a system. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073