Seeking help with deteriorating performance of TrueNAS as a vSphere storage backend

[morganL]

I was forcefully advocating to overprovision. I got blown off big time, I believe directly by Jordan, with a "come back when you have statistics to prove this."

It wouldn't be the first time that they refused to implement something I suggested and then did it later on.

I'm actually still curious where the incorrect term "overprovision" grew out of. Typically when you undersize things, such as limiting a circuit capable of 1Gbps down to 900Mbps, this is referred to as "underprovisioning" in the industry. The incorrect "overprovision" seemed to pop up around 2015-2016 and may have come from the gamers. Either way, I talked about it X-provisioning often enough.

I started "over provisioning" flash systems back in about 2010. From the flash/ssd vendors perspective, they provisioned much more flash than the advertised drive size. More over provisioning provided more speed (for sustained writes).

When a user then reconfigures to reduce the effective drive size with same amount of flash.... then I can see that "Under provisioning" also makes sense.

Jordan and you were both probably right... but for different use-cases.

 

[jgreco]

Jordan and you were both probably right... but for different use-cases.

What use case would that be? Blowing off someone who makes a technically correct suggestion that could increase performance doesn't count as a use case, at least as I understand the term.

Jordan wasn't right. He just blew me off and closed the ticket. Then apparently some years later, iXsystems went and implemented what I had suggested. This reinforces the theory that I was correct and Jordan was not.

There was a reason I eventually stopped submitting bug reports.

<frustration />

 

[morganL]

What use case would that be? Blowing off someone who makes a technically correct suggestion that could increase performance doesn't count as a use case, at least as I understand the term.

Jordan wasn't right. He just blew me off and closed the ticket. Then apparently some years later, iXsystems went and implemented what I had suggested. This reinforces the theory that I was correct and Jordan was not.

There was a reason I eventually stopped submitting bug reports.

<frustration />

Hope Kris and I are better that way... (that's an invitation to flame )

 

[jgreco]

Hope Kris and I are better that way... (that's an invitation to flame )

I haven't had any particularly negative things to say since Jordan and a few others left. Some of the Jordan ire predates iXsystems FreeNAS by 15 years. I think you know I'm probably going to say what's on my mind, but even with the advent of SCALE, I at least understand most of why you folks do what you do, and that's pretty good. Kris has an awesome reputation but my direct exposure has been almost zero. You're also fine even if you seem to be more of a Linux proponent. Flame-y enough?

 

[iigx]

@Ericloewe , @jgreco , @morganL , @NickF , @Arwen
Thank you so much for your positive discussion of my current troubles. I really appreciate it.
Your discussion makes me feel like I don't know anything about TrueNAS, the previous configuration was just playing around, and now it's broken...
I have requested a second storage server with the same configuration from my boss, so now I got the chance to migrate those virtual machines without downtime and completely reconfigure the storage server to a more rational configuration one by one.
So now I have two servers with the following configuration and can configure them from scratch:
- DELL R740XD
- CPU: 1xIntel 4210R
- RAM: 128G ECC
- 24*4TB Samsung EVO SSD (at least one SSD is required as the system disk)
I have read through the advice you have given, and now I have the following considerations:
- Use TrueNAS Core rather than TrueNAS Scale
- Although performance is important, the size of storage space is still very important to me, so mirror of disk has a lower priority for me
- Change the layout from 1 RAIDZ3 vdev to multiple vdev then include in single data pool
- Change the sync to Disabled
- Switch from iSCSI to NFS
Can you give me more suggestions, such as specific ZFS layout, data pool configuration, any corrections to the above items and direct suggestions are welcome.

 

[NickF]

You know, IXSystems does sell systems and will help you min/max to the best of their ability with your budget, right? :P

Before you go out and buy another R740, that might be worth considering. Then you will have actual support.

 

[iigx]

You know, IXSystems does sell systems and will help you min/max to the best of their ability with your budget, right? :P

Before you go out and buy another R740, that might be worth considering. Then you will have actual support.

Thank you @NickF , I read through some threads and recommended documents, i should consider the mirror stripe to improve the IOPS, use NFS to save the space, this is what I think of as the capacity and performance solution at the moment.
You guys are really nice and helped me a lot.