Performance Issues with Windows VMs

[gooni]

Good morning,

we have performance problems with our installed Windows 2019 servers, which show up in the fact that programs start and interact very slowly.

For example the SQL Management Studio takes about 30 seconds to start or if we click on masks in our ERP system (SQL Server), these load up to 10 seconds. We implemented all best practises for Windows.

Our hardware:

- HP Proliant DL360 Gen9 with 32 CPU Cores ( E5-2683 V4) and 96 GB RAM.
- QNAP TS463U RAID10 with WD RED Harddisks as Diskstorage
- The storage is connected to the NAS with 10 Gbit (Switch)

agent: 1
balloon: 0
boot: order=virtio1;ide2;ide0;net0
cores: 4
cpu: host
ide0: none,media=cdrom
ide2: none,media=cdrom
machine: pc-i440fx-5.2
memory: 16384
name: TS01
net0: virtio=42:E5:8B:A6:2F:1F,bridge=vmbr0,firewall=1
numa: 1
ostype: win10
scsihw: virtio-scsi-pci
smbios1: uuid=7e3049b9-b21f-4a26-a13e-784d41ee92b7
sockets: 1
virtio1: ProxmoxDS1:101/vm-101-disk-0.raw,cache=writeback,discard=on,size=80G
vmgenid: 155afe86-2253-467f-a80a-ba528171613d

We can´t figure out where the bottleneck is. Í think it´s the CPU, but there isn´t very high load in the VM or Node. Maybe it is helpful when we delete the local-lvm and move the storage to the node? Any suggestion would be helpful

Thanks

 

[VoIP-Ninja]

Bottleneck = WD Red Spinners. You should try enterprise SSDs for better performance. Your crystalmark is benchmarking your RAM …

 

[gooni]

Bottleneck = WD Red Spinners. You should try enterprise SSDs for better performance. Your crystalmark is benchmarking your RAM …

Thanks. Or should we try to move the disks to the local host storage (SAS) ?

Why do you think crystalmark ist benchmarking my RAM?

 

[entilza]

2019 SQL Management Studio loads very slow I have same issue, with SSDs. I don't think it's an issue, second load is much faster.

I read some threads about speeding it up here. https://www.sqlservercentral.com/forums/topic/ssms-v-18-slow-is-it-me-or

For me the initial load is slow, I just leave it running in background sometimes.

My SQL Manager is fast once it's loaded so perhaps the drives are causing it to be slow once you are in..

PS. I don't run crystal disk anymore, I had bad experience with it on ZFS using too much memory and it once rebooted my server! (OOM killer kicked in) Haven't had any issues with these servers for 6 months afterwards.

 

[Dunuin]

Why do you think crystalmark ist benchmarking my RAM?

Because you are using writeback caching and CrystalDiskMark is only doing async writes. So everything is cached in RAM (you only read/write 5x 1GB so thats no problem with 96GB of RAM) and you don't see any real performance. Using random 4K sync writes without queuing you most likely drop down to something in the KB/s range.

Fio is a way better tool for disk benchmarking. You can refer to the ZFS SSD benchmark paper for which options to use.