Romex Software Forum

Hello, I have production Hyper-V with this configuration:
CPU: Intel 9900k
RAM: 128 GB DDR4 non-ECC
Drives:
2x Tohiba 10 TB HDD (TOSHIBA MG06ACA10TEY 10000.8 GB)
2x Samsung 1 TB SSD NVMe PCIe 3.0 (SAMSUNG MZVLB1T0HALR-00000 1024.2 GB)
OS: MS Windows Server wirh Hyper-V and Storage roles

Volumes configuration:
2xHDD's are in program RAID-1 array
2xSSD's are in program RAID-1 array
10% of HDD is drive C: (NTFS)
90% is drive D: (ReFS)
90% of SSD is drive E: (ReFS+deduplication)
10% (75GB) of SSD is PrimoCache L2 volume

PrimoCache configuration:
L1 Read = 100%, 32 GB
l2 Write = 100%, 75 GB
gather = default
defer-write = 16KB, 10sec, intelligent

My workload is Windows Remote Desktop Servers with MS SQL and MySQL and databases. 95 of databases are laying into SSD drives. Also most of big data used just for backups and rarely used data. Obviously I cannot use L1 for write, but what's the best practices for my configuration?
2) Is there some sense to use L1 for read-only?
3) How soon NVMe SSD will die when it's set as cache?
4) Have idea to add RAM as read-only cache for SSD. Is it useful?

P.S. I'll attack more screenshots after tomorrow business day after workload.

I'm sorry for the late reply because there are too many support tickets these days. Regarding your scenario, please note that whether you use L1 or L2 for Defer-Write, the risk of data loss from a sudden power loss or system crash/freeze is the same. Please see https://www.romexsoftware.com/en-us/pri ... write.html

And we currently do not recommend caching on Refs volumes.

Support wrote: ↑Sun Jun 04, 2023 9:12 am And we currently do not recommend caching on Refs volumes.

May I ask why?

I am running Primo cache on ReFS for VM caching on Windows 2019. Already for years.
Never ran into an issue ....

tverweij wrote: ↑Wed Jun 14, 2023 5:13 pm May I ask why?

I am running Primo cache on ReFS for VM caching on Windows 2019. Already for years.
Never ran into an issue ....

Some users once reported that data corruption occurred on the ReFS system with PrimoCache. We have tested for a long time but have not yet reproduced the problem. At present, we don't know exactly what triggers this issue, so to be on the safe side we recommend NTFS or FAT32 file systems.

tverweij wrote: ↑Wed Jun 14, 2023 5:13 pm May I ask why?

I am running Primo cache on ReFS for VM caching on Windows 2019. Already for years.
Never ran into an issue ....

Most of the versions with the problem reported are 3.x~4.0. We are not sure whether the current version still has the problem. It's also possible that since ReFS has had some updates, the problem doesn't exist anymore.

For ReFS:

1. Only use it on a server - never on workstations - it was not designed for that.
2. Never use ReFS on Windows 2016 or below, only on 2019 and above. It became stable in Windows 2019.

tverweij wrote: ↑Thu Jun 15, 2023 5:19 pm For ReFS:

1. Only use it on a server - never on workstations - it was not designed for that.
2. Never use ReFS on Windows 2016 or below, only on 2019 and above. It became stable in Windows 2019.

Thank you for sharing your experience!