NVMe Cache worth it?

[Xalciodra]

Good afternoon,

 

Currently we have a small Hyper-V Cluster running with +/- 30VMs.

50% of this is intensively used as a SQL or RDS server.
The other 50% is DNS, Domain controller, web server,..

 

The Cluster is connected to a synology NAS via ISCSI.

4x SSD RAID 5 - SAT5200-960G

 

Is it useful to use 2x NVMe storage as cache on this synology? (Read Only cache)

2x NVME RAID 0 - Samsung 970PRO

 

Will this allow you to work much more efficiently?
I have no experience with this at all.

 

Kind Regards,

[Electronics Wizardy]

What is the disk utilization? How many iops are you seeing?

 

This feels like a ask your team or consultant question as this is for work, and not a cheap setup.

[Xalciodra]

3 minutes ago, Electronics Wizardy said:

What is the disk utilization? How many iops are you seeing?

 

This feels like a ask your team or consultant question as this is for work, and not a cheap setup.

I can't see that right now.

We want to centralize everything.

I'd really just like to know if an NVMe cache would give better performance when already working with SATA SSDs.

 

[Electronics Wizardy]

3 minutes ago, Xalciodra said:

I can't see that right now.

We want to centralize everything.

I'd really just like to know if an NVMe cache would give better performance when already working with SATA SSDs.

 

Well its hard to say if the performance would be better without knowing more info. 

 

Id be tempted to go optane if you can as the qd1 iops and latency is much better than any nand drive.

 

What model nas are you using? What network speed?

 

 

[Xalciodra]

1 minute ago, Electronics Wizardy said:

Well its hard to say if the performance would be better without knowing more info. 

 

Id be tempted to go optane if you can as the qd1 iops and latency is much better than any nand drive.

 

What model nas are you using? What network speed?

 

 

I understand that! =)

Synology RS1619xs+
2x 10Gbps bonded

[Electronics Wizardy]

Just now, Xalciodra said:

I understand that!

Synology RS1619xs+
2x 10Gbps bonded

Are you disk io limited? What latency and iops are you seeing? What queue depth are the drives running at?

 

The cache probably won't hurt, but its really hard to say how much without more info. 

 

Id really hire someone that knows what their doing to help you here.

[Xalciodra]

@Electronics Wizardy
I found this online, i don't think the NVMe cache is usefull for this model.
Performance | Synology Incorporated

[Electronics Wizardy]

4 minutes ago, Xalciodra said:

@Electronics Wizardy
I found this online, i don't think the NVMe cache is usefull for this model.
Performance | Synology Incorporated

What makes you say that from this document? It only lists 1gbe performance, not 10gbe, and doesn't have a ssd cached by ssd config.

 

What is the usage like on the synology? Disk usage? CPU usage? queue depth? Id look at your unit more first.

[Thirdgen89GTA]

NVMe cache is not likely to provide any real benefit.  You'd need something like an enterprise grade Octane drive.  And it would have to be sized appropriately to hold all the active data. You are also at the mercy of the Sinology cache algorithm.

 

Honestly, the fact that you are running 30+ VM's off that is insane. You should have built an enterprise grade solution ages ago.