CPU sockets/cores. How to assing all cores? How to speed up disk speed?

[marshy]

Hey!

So here is a node itself:

Basic System Information:
---------------------------------
Processor : AMD EPYC 7313 16-Core Processor
CPU cores : 32 @ 1500.000 MHz
AES-NI : ✔ Enabled
VM-x/AMD-V : ✔ Enabled
RAM : 62.8 GiB
Swap : 0.0 KiB
Disk : 1.7 TiB

fio Disk Speed Tests (Mixed R/W 50/50):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 973.22 MB/s (243.3k) | 1.48 GB/s (23.1k)
Write | 975.79 MB/s (243.9k) | 1.49 GB/s (23.3k)
Total | 1.94 GB/s (487.2k) | 2.97 GB/s (46.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 1.87 GB/s (3.6k) | 1.92 GB/s (1.8k)
Write | 1.97 GB/s (3.8k) | 2.05 GB/s (2.0k)
Total | 3.85 GB/s (7.5k) | 3.98 GB/s (3.8k)

iperf3 Network Speed Tests (IPv4):
---------------------------------
Provider | Location (Link) | Send Speed | Recv Speed
| | |
Clouvider | London, UK (10G) | 974 Mbits/sec | 8.18 Gbits/sec
Online.net | Paris, FR (10G) | 976 Mbits/sec | 8.20 Gbits/sec
Clouvider | NYC, NY, US (10G) | 921 Mbits/sec | 2.10 Gbits/sec

Geekbench 4 Benchmark Test:
---------------------------------
Test | Value
|
Single Core | 6090
Multi Core | 70778
Full Test | https://browser.geekbench.com/v4/cpu/16526240

Geekbench 5 Benchmark Test:
---------------------------------
Test | Value
|
Single Core | 1387
Multi Core | 18104
Full Test | https://browser.geekbench.com/v5/cpu/14129066

And here is a VM:

Basic System Information:
---------------------------------
Processor : AMD EPYC 7313 16-Core Processor
CPU cores : 32 @ 3000.006 MHz
AES-NI : ✔ Enabled
VM-x/AMD-V : ✔ Enabled
RAM : 15.6 GiB
Swap : 0.0 KiB
Disk : 20.0 GiB

fio Disk Speed Tests (Mixed R/W 50/50):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 552.17 MB/s (138.0k) | 5.10 GB/s (79.7k)
Write | 553.62 MB/s (138.4k) | 5.12 GB/s (80.1k)
Total | 1.10 GB/s (276.4k) | 10.23 GB/s (159.8k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 5.15 GB/s (10.0k) | 5.47 GB/s (5.3k)
Write | 5.43 GB/s (10.6k) | 5.83 GB/s (5.6k)
Total | 10.59 GB/s (20.6k) | 11.30 GB/s (11.0k)

iperf3 Network Speed Tests (IPv4):
---------------------------------
Provider | Location (Link) | Send Speed | Recv Speed
| | |
Clouvider | London, UK (10G) | 974 Mbits/sec | 8.71 Gbits/sec
Online.net | Paris, FR (10G) | 976 Mbits/sec | 7.53 Gbits/sec
Clouvider | NYC, NY, US (10G) | 915 Mbits/sec | 1.91 Gbits/sec

Geekbench 4 Benchmark Test:
---------------------------------
Test | Value
|
Single Core | 5971
Multi Core | 60857
Full Test | https://browser.geekbench.com/v4/cpu/16526228

Geekbench 5 Benchmark Test:
---------------------------------
Test | Value
|
Single Core | 1402
Multi Core | 15634
Full Test | https://browser.geekbench.com/v5/cpu/14128941

So as you can see there is a difference in speed in 4k blocks and geekbench showing less multicore "power".

Current setup for CPU: 1 socket, 32 cores, all others on default.
Disks: VirtIO-block / Write back.

My question is if I do correctly assign all cores? Why then there is such multicore difference?
And the second one is there a possibility to improve 4k blocks disk speed?

Cheers!

 

[Dunuin]

You didn't showed us your storage or VM configs. What storage are you using? ZFS for examples defaults with a 8K volblocksize and virtio disks will use 512B sectors by default. So when doing 4K writes to a 8K virtual disk you should loose 50% performance.

 

[marshy]

You didn't showed us your storage or VM configs. What storage are you using? ZFS for examples defaults with a 8K volblocksize and virtio disks will use 512B sectors by default. So when doing 4K writes to a 8K virtual disk you should loose 50% performance.

Here you go. Using basic - directory.

In LXC i'm getting this:

fio Disk Speed Tests (Mixed R/W 50/50):
---------------------------------
Block Size | 4k (IOPS) | 64k (IOPS)
------ | --- ---- | ---- ----
Read | 661.10 MB/s (165.2k) | 3.62 GB/s (56.6k)
Write | 662.85 MB/s (165.7k) | 3.64 GB/s (56.9k)
Total | 1.32 GB/s (330.9k) | 7.26 GB/s (113.5k)
| |
Block Size | 512k (IOPS) | 1m (IOPS)
------ | --- ---- | ---- ----
Read | 1.66 GB/s (3.2k) | 3.81 GB/s (3.7k)
Write | 1.75 GB/s (3.4k) | 4.06 GB/s (3.9k)
Total | 3.41 GB/s (6.6k) | 7.88 GB/s (7.6k)