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.
-
@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.
-
@dashrender said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@scottalanmiller said in SAS SSD vs SAS HDD in a RAID 10?:
@dave247 said in SAS SSD vs SAS HDD in a RAID 10?:
@dustinb3403 said in SAS SSD vs SAS HDD in a RAID 10?:
OBR5 is the standard if you are going to be using an SSD
Are there any good sources that express that as best practice? I'm looking for myself now too and by the way....
There can never be a best practice of this sort. It's standard practice to start with RAID 5 for SSD due to the risk types and levels, but not on HDs for the same reason. RAID 10 tends to saturate RAID controllers with SSD, but not with HDs.
As with all RAID, it comes down to price / risk / performance. And for most deployments, RAID 5 gives the best blend with SSDs; and RAID 10 gives the best blend for HDs. But in both cases, RAID 6 is the second most popular choice, and RAID 10 is an option with SSDs.
With SSDs, you rarely do RAID 10. If you really need the speed, you tend to do RAID 1 with giant NVMe cards instead.
Yeah, sorry, I guess I shouldn't have said "best practice". I was more or less looking for some information that would help validate what Dustin said. I wanted to look into it more and educate myself as much as possible.
Well I think if I am able to go with the SSD drives, I will do a RAID 6. I am creating a few different server builds as options that display different levels of performance and cost.
Speaking of my RAID card, I am looking at the H740P which has 8GB of NV cache memory and flash backed cache. I still need to educate myself on this stuff as well because I'm not sure if this is overkill or not. My other option was the H330, which has none of that.
EDIT: Nevermind on the H330 doesn't offer RIAD 6 as an option.
Dave - why do you trust HDD in RAID 10, but don't trust Enterprise SSD drives in RAID 5?
This really boils down to math. The URE rate of Enterprise SSD drives starts one level higher than that of HDDs, which is the reason that Scott started preaching SSDs in RAID 5 years ago.
As you said - definitely dive into the whys and you'll see that unless your needs are very special, it's pretty likely that RAID 5 SSDs will do the job for you.
But all that is really moot until you know what your real requirements are. If you need 10,000 IOPs, can you even reasonably get that from HDDS in RAID 10? what if you need 100,000 or 1 million?
This information is way more important to know before you look at what to buy, because it basically tells you were to look to get the parts to meet the goal.
I really like the read & write gains of RAID 10 but that's been with spindle drives. Now that I'm considering SSD, I was trying to determine if RAID 10 was appropriate or not. I got some feedback from others explaining that RAID 5/6 was a better choice than 10 for SSD arrays.
I'm not exactly certain on the amount of IOPs but this is for a "heavy-hitting" SQL document management database server with 2TB+ of files from over the last decade. We have seen performance issues in the past but most have been due to other factors not relating to storage config. That being said, I think upgrading and improving the storage config will still dramatically improve performance for us. Either way, our current server is EOL soon (both hardware and software) so that's the primary reason for upgrading.
-
@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.
-
@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.
-
@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?
-
@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.
-
@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?
-
@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!
-
@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.
-
@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
-
BTW: why are we calling hard drives "Winchester drives"?
-
@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
-
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..
-
@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.
-
@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?
-
@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.
-
@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.
