SSD for VM server

[KirbyTech]

I just got offered a cheap server from work that is a Dell R710 SFF with the 8 bay 2.5" drives. It has decent specs 2x 6 core with HT and 144 GB of RAM. Comes with no drive though. I was thinking since we put SSDs into our workstations that putting some into the server would be a great way to speed up the VMs. Maybe it would be better to shell out for the expensive 2.5" HDDs as boot drives then do SSD based data-stores for stuff like DBs, cache drives ect

 

 

[Mikensan]

If you can put an HBA instead of a RAID controller (or if the controller supports it, IT mode) and let the O/S handle TRIM / garbage collection for the SSDs, that's fine to do. At least you would put your heavy I/O VMs on the SSDs and things like a domain controller or appliances that run in RAM (firewalls) on spinners. 

 

However if you plan to use a Perc 6 or H700, I'd advise against using SSDs. Also if your hypervisor supports it, boot off of a USB stick, or if the R710 has it, micro-SD. Open the lid and look towards the front of the case, might be a USB port and MicroSD slot. 

[KirbyTech]

On 2/15/2018 at 4:44 PM, Mikensan said:

If you can put an HBA instead of a RAID controller (or if the controller supports it, IT mode) and let the O/S handle TRIM / garbage collection for the SSDs, that's fine to do. At least you would put your heavy I/O VMs on the SSDs and things like a domain controller or appliances that run in RAM (firewalls) on spinners. 

 

However if you plan to use a Perc 6 or H700, I'd advise against using SSDs. Also if your hypervisor supports it, boot off of a USB stick, or if the R710 has it, micro-SD. Open the lid and look towards the front of the case, might be a USB port and MicroSD slot. 

I was going to upgrade to the H700. Why not go with SSDs?

 

My hypervisor is ESXi 6.5 u1 so I should will be booting from USB as that is the best way to be. No mico-SD (I know of) sadly but not a bit difference really.

[leadeater]

9 hours ago, KirbyTech said:

I was going to upgrade to the H700. Why not go with SSDs?

Because unless it's a server/enterprise SSD it'll mostly likely not perform properly and die an early death, ESXi really murders SSDs because it doesn't have proper TRIM functionality for local SSDs.

 

My Samsung 840 and 850 Pros just don't like it, performs worse than an HDD. You can prevent that performance drop with a 20% OP but you'll still be causing early death to them.

[Dark]

And definitely take @Mikensans suggestion to boot ESXI from a USB thumbdrive.  No point in losing a disk bay if you don't have to.

 

As for SSD, I've been using them in my cluster for awhile now (2x 1TB 840 Evo, no raid, just two datastores, and an array of 2TB 850 Pros hosted by a QNAP).  I haven't noticed any performance issues with the single SSD datastores.

 

ESXi does support unmap and most recent SSDs have decent garbage collection.  

 

As for the raid controller, present SSDs in pass-through mode (set them as non-raid if there is no pass-through option) and create an array from spinning disks.

[leadeater]

1 hour ago, Dark said:

As for SSD, I've been using them in my cluster for awhile now (2x 1TB 840 Evo, no raid, just two datastores, and an array of 2TB 850 Pros hosted by a QNAP).  I haven't noticed any performance issues with the single SSD datastores.

 

ESXi does support unmap and most recent SSDs have decent garbage collection.

The unmap is part of the SCSI standard but it's still not clear if proper TRIM support is actually working in ESXi and VMware has never been clear on it. Also unmap is there mostly for VAAI integration with external disk arrays which makes the matter even less clear as to what is actually happening to a local SSD.

 

Externally my 850 Pros over ISCSI and NFS to the ESXi host work fine just not locally on an LSI RAID card, the 6 will push 2GB/s read and 1.5GB/s write over dual path 10Gb.

 

The main issue is it can be hard to spot something is wrong with the SSDs as the IOPs stay rather good (but drop significantly from spec) and ESXi does a fair decent job at I/O caching but if you force an unbuffered disk write you get 60MB/s max. If you take the SSDs out and clean them on a Windows computer and force a GC then put them back in the ESXi host they do 500MB/s again for about 30 minutes to an hour.

 

I forget all the combinations of tests I did but without fail they would slow down unless I did a 20% OP when creating the datastore, which is about the extra internal OP Samsung puts on the enterprise SSDs anyway 480GB SM863 = 512GB Pro

[iJarda]

2 hours ago, leadeater said:

I forget all the combinations of tests I did but without fail they would slow down unless I did a 20% OP when creating the datastore, which is about the extra internal OP Samsung puts on the enterprise SSDs anyway 480GB SM863 = 512GB Pro

Recently I got my SM863, so as you say, it should be OK in ESXi? (R730 directly to SATA, without RAID card) (I haven't tried yet)

[leadeater]

3 minutes ago, iJarda said:

Recently I got my SM863, so as you say, it should be OK in ESXi? (R730 directly to SATA, without RAID card) (I haven't tried yet)

Yea it'll be fine, it's the same SSD in our Nutanix servers that are running ESXi, we have a good 40 or so so I know it's good.

[KirbyTech]

4 hours ago, Dark said:

And definitely take @Mikensans suggestion to boot ESXI from a USB thumbdrive.  No point in losing a disk bay if you don't have to.

 

As for SSD, I've been using them in my cluster for awhile now (2x 1TB 840 Evo, no raid, just two datastores, and an array of 2TB 850 Pros hosted by a QNAP).  I haven't noticed any performance issues with the single SSD datastores.

 

ESXi does support unmap and most recent SSDs have decent garbage collection.  

 

As for the raid controller, present SSDs in pass-through mode (set them as non-raid if there is no pass-through option) and create an array from spinning disks.

This server will have no HDDs if all goes as planned. I have a storage servers (15 x 10TB and 12 x 8TB) that handle everything, I am simply planning this server as an application and database host.

 

Not planning to run any RAID on this host, all data is backed going to be like the rest of my servers, backed up on the hour, 6 hour, 1 day, 1 week and 1 month marks, with a staggered retention so I never have more than 12 hourly, 8 x 6 hours, 7 days, 4 weeks and 3 months. 

[leadeater]

2 hours ago, KirbyTech said:

This server will have no HDDs if all goes as planned. I have a storage servers (15 x 10TB and 12 x 8TB) that handle everything, I am simply planning this server as an application and database host.

 

Not planning to run any RAID on this host, all data is backed going to be like the rest of my servers, backed up on the hour, 6 hour, 1 day, 1 week and 1 month marks, with a staggered retention so I never have more than 12 hourly, 8 x 6 hours, 7 days, 4 weeks and 3 months. 

In that case how much storage do you need? There's some great deals on Amazon right now for the prevision revision PM863/SM863 (non a i.e PM863a), PM will be more than fine.

 

https://www.amazon.com/Samsung-Pm863-Internal-Maximum-Transfer/dp/B013FDAENQ/ref=sr_1_1?ie=UTF8&qid=1518930498&sr=8-1&keywords=PM863&dpID=519RgWqJGUL&preST=_SY300_QL70_&dpSrc=srch

 

Server rated 960GB SSD for $315 is bloody good in my opinion, which is a lot less than a 1TB 860 Pro

[KirbyTech]

9 hours ago, leadeater said:

In that case how much storage do you need? There's some great deals on Amazon right now for the prevision revision PM863/SM863 (non a i.e PM863a), PM will be more than fine.

 

https://www.amazon.com/Samsung-Pm863-Internal-Maximum-Transfer/dp/B013FDAENQ/ref=sr_1_1?ie=UTF8&qid=1518930498&sr=8-1&keywords=PM863&dpID=519RgWqJGUL&preST=_SY300_QL70_&dpSrc=srch

 

Server rated 960GB SSD for $315 is bloody good in my opinion, which is a lot less than a 1TB 860 Pro

For storage I figure I will want 2-4 tb sadly that deal you posted I can't get. I am in Canada so our prices are crazy.

[leadeater]

4 hours ago, KirbyTech said:

For storage I figure I will want 2-4 tb sadly that deal you posted I can't get. I am in Canada so our prices are crazy.

Odd, I'm able to purchase that from NZ.

[AshleyAshes]

4 hours ago, KirbyTech said:

For storage I figure I will want 2-4 tb sadly that deal you posted I can't get. I am in Canada so our prices are crazy.

 

5 minutes ago, leadeater said:

Odd, I'm able to purchase that from NZ.

I'm in Canada and I have problem ordering that to my Canadian address.

 

[Mikensan]

How about newegg? https://www.newegg.com/Product/Product.aspx?Item=9SIA5AD6SX3928&cm_re=Pm863_960-_-20-147-415-_-Product