SAS SSD vs SAS HDD in a RAID 10?
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@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@darek-hamann said in SAS SSD vs SAS HDD in a RAID 10?:
Before the RAID array type is selected, it would be great to know the workload in terms of write operations. For RAID5/6 write performance will be significantly lower than that of RAID10 on the same disks. Just bear that in mind.
Right, but compared to today, we are writing to six 10K RPM drives in a RAID5 config. This server is something like 6 years old and performance is acceptable. Going to new hardware, especially faster RPM drives or SSD drives will be a significant improvement.
OK I guess that's a good enough baseline then.
A RAID 1 two 4 TB SATA/SAS SSDs would crush your current system and save you a bundle.
Yeah, I was wondering that same thing actually. If I just purchased two 4TB 7.2K RPM 6Gbps SATA drives, would that actually be better than my current config as well as have the same level of reliability as the SAS drives?
I wanted to go with SSD since they are obviously way faster and last longer, in the event that we don't upgrade again for another 7 years or something.
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@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dustinb3403 said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s except the cost per GB is even more for U.2 drives than it is for the traditional formats.
Depends on how you calculate. One NVMe drive, say 4TB, it will beat the performance of four 1TB SATA SSD drives in RAID0. If you take 4x1TB drives and a raid controller the 4TB NVMe will be cheaper or similar. So per IOPS the NVMe drives are cheaper. And total failure rate is lower because you need fewer drives to accomplish the same thing.
If you on the other side take a 4TB NVMe drive compared to a 4TB SATA SSD you will pay about 25% premium for the NVMe drive. Intel for instance have their DC series of drives that are available both in SATA and NVMe which makes it easier to compare apples to apples.
Except in your RAID example above you totally miss that the OP wants hardware protection. So a RAID card is required regardless (either onboard real RAID 1 for your dual drive setup, or add-in card).
I didn't miss it, I just compared it performance wise. You could do RAID1 with two NVME drives but that would be some something like Intel RST (motherboard) so low cost. If you want a RAID controller that can come close to that, you need something very expensive, and then the 8x1TB SSD in RAID10 to go with it.
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@darek-hamann said in SAS SSD vs SAS HDD in a RAID 10?:
Before the RAID array type is selected, it would be great to know the workload in terms of write operations. For RAID5/6 write performance will be significantly lower than that of RAID10 on the same disks. Just bear that in mind.
Right, but compared to today, we are writing to six 10K RPM drives in a RAID5 config. This server is something like 6 years old and performance is acceptable. Going to new hardware, especially faster RPM drives or SSD drives will be a significant improvement.
OK I guess that's a good enough baseline then.
A RAID 1 two 4 TB SATA/SAS SSDs would crush your current system and save you a bundle.
Yeah, I was wondering that same thing actually. If I just purchased two 4TB 7.2K RPM 6Gbps SATA drives, would that actually be better than my current config as well as have the same level of reliability as the SAS drives?
I wanted to go with SSD since they are obviously way faster and last longer, in the event that we don't upgrade again for another 7 years or something.
Absolutely not.
it's all about IOPs - A single 7.2K RPM SATA drive gives you something like 75 IOPs. That might be enough for you to run things on a desktop, but on a server, you'll be super unhappy.
You currently have six 10K RPM drives (let's assume you're getting 130 IOPs per drive). The RAID 5 you have has huge write penalties too.
I'm guessing you're probably getting around 260 IOPs of write, and maybe 520 IOPs of read (at max).
Now compare this to a two drive RAID 1 7.2K RPM array - remember, 7.2K drives only give you 75 IOPs. For Read we might get 2*75 = 150, for Write we only get one drive worth, or 75 IOPs.
A single Enterprise SSD likely gives you 25,000 IOPs on the low end (very low end) So a RAID 1 (two drives) 4 TB SSD array could give you 50,000 IOPs of Read and 25,000 of Write.
See the huge differences here?
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@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@darek-hamann said in SAS SSD vs SAS HDD in a RAID 10?:
Before the RAID array type is selected, it would be great to know the workload in terms of write operations. For RAID5/6 write performance will be significantly lower than that of RAID10 on the same disks. Just bear that in mind.
Right, but compared to today, we are writing to six 10K RPM drives in a RAID5 config. This server is something like 6 years old and performance is acceptable. Going to new hardware, especially faster RPM drives or SSD drives will be a significant improvement.
OK I guess that's a good enough baseline then.
A RAID 1 two 4 TB SATA/SAS SSDs would crush your current system and save you a bundle.
Yeah, I was wondering that same thing actually. If I just purchased two 4TB 7.2K RPM 6Gbps SATA drives, would that actually be better than my current config as well as have the same level of reliability as the SAS drives?
I wanted to go with SSD since they are obviously way faster and last longer, in the event that we don't upgrade again for another 7 years or something.
Absolutely not.
@dave247, @dashrender said two 4TB SATA/SAS SSDs in RAID1, not HDDs.
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@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dustinb3403 said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s except the cost per GB is even more for U.2 drives than it is for the traditional formats.
Depends on how you calculate. One NVMe drive, say 4TB, it will beat the performance of four 1TB SATA SSD drives in RAID0. If you take 4x1TB drives and a raid controller the 4TB NVMe will be cheaper or similar. So per IOPS the NVMe drives are cheaper. And total failure rate is lower because you need fewer drives to accomplish the same thing.
If you on the other side take a 4TB NVMe drive compared to a 4TB SATA SSD you will pay about 25% premium for the NVMe drive. Intel for instance have their DC series of drives that are available both in SATA and NVMe which makes it easier to compare apples to apples.
Except in your RAID example above you totally miss that the OP wants hardware protection. So a RAID card is required regardless (either onboard real RAID 1 for your dual drive setup, or add-in card).
I didn't miss it, I just compared it performance wise. You could do RAID1 with two NVME drives but that would be some something like Intel RST (motherboard) so low cost. If you want a RAID controller that can come close to that, you need something very expensive, and then the 8x1TB SSD in RAID10 to go with it.
Why are you doing SSD RAID 10? just to try to come close performance wise to the NVMe?
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@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@darek-hamann said in SAS SSD vs SAS HDD in a RAID 10?:
Before the RAID array type is selected, it would be great to know the workload in terms of write operations. For RAID5/6 write performance will be significantly lower than that of RAID10 on the same disks. Just bear that in mind.
Right, but compared to today, we are writing to six 10K RPM drives in a RAID5 config. This server is something like 6 years old and performance is acceptable. Going to new hardware, especially faster RPM drives or SSD drives will be a significant improvement.
OK I guess that's a good enough baseline then.
A RAID 1 two 4 TB SATA/SAS SSDs would crush your current system and save you a bundle.
Yeah, I was wondering that same thing actually. If I just purchased two 4TB 7.2K RPM 6Gbps SATA drives, would that actually be better than my current config as well as have the same level of reliability as the SAS drives?
I wanted to go with SSD since they are obviously way faster and last longer, in the event that we don't upgrade again for another 7 years or something.
Absolutely not.
@dave247, @dashrender said two 4TB SATA/SAS SSDs in RAID1, not HDDs.
Exactly. A RAID 1 SSD pair - be it SAS/SATA or NVMe will just crush the current storage system you have in place.
current system = 260/520 IOPs
RAID 1 SSD = 25,000/50,000 IOPs. -
@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@darek-hamann said in SAS SSD vs SAS HDD in a RAID 10?:
Before the RAID array type is selected, it would be great to know the workload in terms of write operations. For RAID5/6 write performance will be significantly lower than that of RAID10 on the same disks. Just bear that in mind.
Right, but compared to today, we are writing to six 10K RPM drives in a RAID5 config. This server is something like 6 years old and performance is acceptable. Going to new hardware, especially faster RPM drives or SSD drives will be a significant improvement.
OK I guess that's a good enough baseline then.
A RAID 1 two 4 TB SATA/SAS SSDs would crush your current system and save you a bundle.
Yeah, I was wondering that same thing actually. If I just purchased two 4TB 7.2K RPM 6Gbps SATA drives, would that actually be better than my current config as well as have the same level of reliability as the SAS drives?
I wanted to go with SSD since they are obviously way faster and last longer, in the event that we don't upgrade again for another 7 years or something.
Absolutely not.
@dave247, @dashrender said two 4TB SATA/SAS SSDs in RAID1, not HDDs.
ugh yeah this is my mistake. I missed that. Disregard!
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@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s said in SAS SSD vs SAS HDD in a RAID 10?:
@dustinb3403 said in SAS SSD vs SAS HDD in a RAID 10?:
@pete-s except the cost per GB is even more for U.2 drives than it is for the traditional formats.
Depends on how you calculate. One NVMe drive, say 4TB, it will beat the performance of four 1TB SATA SSD drives in RAID0. If you take 4x1TB drives and a raid controller the 4TB NVMe will be cheaper or similar. So per IOPS the NVMe drives are cheaper. And total failure rate is lower because you need fewer drives to accomplish the same thing.
If you on the other side take a 4TB NVMe drive compared to a 4TB SATA SSD you will pay about 25% premium for the NVMe drive. Intel for instance have their DC series of drives that are available both in SATA and NVMe which makes it easier to compare apples to apples.
Except in your RAID example above you totally miss that the OP wants hardware protection. So a RAID card is required regardless (either onboard real RAID 1 for your dual drive setup, or add-in card).
I didn't miss it, I just compared it performance wise. You could do RAID1 with two NVME drives but that would be some something like Intel RST (motherboard) so low cost. If you want a RAID controller that can come close to that, you need something very expensive, and then the 8x1TB SSD in RAID10 to go with it.
Why are you doing SSD RAID 10? just to try to come close performance wise to the NVMe?
They are often cheaper.
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@dave247, @dashrender said two 4TB SATA/SAS SSDs in RAID1, not HDDs.
Exactly. A RAID 1 SSD pair - be it SAS/SATA or NVMe will just crush the current storage system you have in place.
current system = 260/520 IOPs
RAID 1 SSD = 25,000/50,000 IOPs.Single midrange NVME drive, Intel DC P4510 4TB
113,500/625,500 IOPSSame drive as above but SATA version, Intel D3 S4510 2TB
35,500/97,000 IOPShttps://www.intel.com/content/www/us/en/solid-state-drives/ssd-nvme-overview-video.html
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BTW: why are we calling hard drives "Winchester drives"?
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
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Mind than ssd cache is ofter disabled by default with raid controllers. Letting ssd perf drop down a lot!!!
Enterprise grade ssds should have power loss protection so you should be safe re-enabling ssd on board cache. Again @scottalanmiller or @JaredBusch know more about this. -
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
Yeah I've already looked up "Winchester drive". I still don't understand why you guys would refer to modern hard disk drives as Winchester drives. That would be like referring to all gasoline vehicles as Model-T's..
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
Yeah I've already looked up "Winchester drive". I still don't understand why you guys would refer to modern hard disk drives as Winchester drives. That would be like referring to all gasoline vehicles as Model-T's..
I don't. Scott does. Because Scott does, a number of other people do also. The term is a correct usage.
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@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
Yeah I've already looked up "Winchester drive". I still don't understand why you guys would refer to modern hard disk drives as Winchester drives. That would be like referring to all gasoline vehicles as Model-T's..
I don't. Scott does. Because Scott does, a number of other people do also. The term is a correct usage.
How is it correct usage?
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
Yeah I've already looked up "Winchester drive". I still don't understand why you guys would refer to modern hard disk drives as Winchester drives. That would be like referring to all gasoline vehicles as Model-T's..
I don't. Scott does. Because Scott does, a number of other people do also. The term is a correct usage.
How is it correct usage?
Just because a once common term has fallen out of common usage, that does not invalidate it as a correct term. This nickname was common, and is no longer so. Doesn't make it wrong. Well, any more wrong than it was to start.
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@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@jaredbusch said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Someone should update this wiki article to be other countries, and @scottalanmiller
https://en.wikipedia.org/wiki/History_of_hard_disk_drives
Yeah I've already looked up "Winchester drive". I still don't understand why you guys would refer to modern hard disk drives as Winchester drives. That would be like referring to all gasoline vehicles as Model-T's..
I don't. Scott does. Because Scott does, a number of other people do also. The term is a correct usage.
How is it correct usage?
Just because a once common term has fallen out of common usage, that does not invalidate it as a correct term. This nickname was common, and is no longer so. Doesn't make it wrong. Well, any more wrong than it was to start.
So it's a nickname, not a technical term? If that's the case, then I'd say it's more confusing than anything since it's an antiquated nickname. Just call them hard disk drives or spindle drives or something. That seems a lot more clear and it still differentiates it from SSD drives.
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
I'm planning the build on a new server. I originally intended on putting 8 x "900GB 15K RPM SAS 12Gbps 512e" drives into a RAID 10 config using an H740P adapter, but then I saw that there are quite a few options for SAS SSD. I haven't really learned too much about the differences of putting SSD in RAID and how it compares to HDD in RAID, so I wanted to see if anyone here (Scott) had any input on the matter.
Example: Would it be worth putting, say, 6 x "1.6TB SSD SAS Mix Use 12Gbps 512e" drives into a RAID 10 instead? Is there a better approach with SSD in RAID?
RAID 6 is the way to go. We lost a server after replacing a drive and it's RAID 10 pair decided to drop out about 5 to 10 minutes into a rebuild.
In our comparison testing 8x 10K SAS drives in RAID 6 has a mean throughput of 800MiB/Second and about 250-450 IOPS per disk depending on the storage stack configuration.
SAS SSD would be anywhere from 25K IOPS per disk to 55K-75K IOPS per disk depending on whether read intensive, mixed use, or write intensive. There are some good deals out there on HGST SSDs (our preferred SAS SSD vendor).
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@phlipelder said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
I'm planning the build on a new server. I originally intended on putting 8 x "900GB 15K RPM SAS 12Gbps 512e" drives into a RAID 10 config using an H740P adapter, but then I saw that there are quite a few options for SAS SSD. I haven't really learned too much about the differences of putting SSD in RAID and how it compares to HDD in RAID, so I wanted to see if anyone here (Scott) had any input on the matter.
Example: Would it be worth putting, say, 6 x "1.6TB SSD SAS Mix Use 12Gbps 512e" drives into a RAID 10 instead? Is there a better approach with SSD in RAID?
RAID 6 is the way to go. We lost a server after replacing a drive and it's RAID 10 pair decided to drop out about 5 to 10 minutes into a rebuild.
In our comparison testing 8x 10K SAS drives in RAID 6 has a mean throughput of 800MiB/Second and about 250-450 IOPS per disk depending on the storage stack configuration.
SAS SSD would be anywhere from 25K IOPS per disk to 55K-75K IOPS per disk depending on whether read intensive, mixed use, or write intensive. There are some good deals out there on HGST SSDs (our preferred SAS SSD vendor).
Yeah, I've decided on RAID 6 if I am able to go with SSD drives. I am building out the server on Dell and purchasing through our VAR when it comes time to order.
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@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
BTW: why are we calling hard drives "Winchester drives"?
Because the platters (bullet holder) have to spin while an arm (hammer) moves to find whatever is needed.
Winchester guns are grand symbols of manual action required. With a lot of moving parts.
Whereas any fully automatic weapon would be like an SSD. No moving parts to find whatever is needed. (Fire bullets)
