Hi everybody, my coworker and I have some decent hardware that would make great 
single servers, and then we through in a 10gb switch with 2x10gbps cards in 4 
boxes.  

We have 2  excellent boxes - super micro board (disabled speed step) with 14 
core intel i9's 7940x's, 128 GB ram (3200),  1tb m.2 samsung 870 evo's, 1tb ssd 
samsung, 1 8TB WD Gold, 1 6TB WD gold.  
Then we have 2 boxes (1 with 8 core i7-9700k, 1 with 6 core i7-8700) 128GB ram 
in one, 64GB ram in the other all 3000MHz with the same 1tb ssd,6tb wd gold, 
8tb wd gold drives as the other boxes and 10gbps cards.

Our problem is performance.  We used the slower boxes for KVM(libvirt) and 
FreeNAS at first which was great performance wise. Then we bought the new super 
micro boxes and converted to oVirt + Gluster and did some basic write test 
using dd writing zero's to files from 1GB up to 50GB and were happy with the 
numbers writing directly to the gluster. But then we stuck a windows VM on it 
and turned it on...I'll stop there..because turning it on stopped any 
performance testing. This thing blew goat cheese. It was so slow the oVirt 
guest agent doesn't even start along with MS SQL server engine sometimes and 
other errors.  

So naturally, we removed the gluster from the equation.  We took one of the 8TB 
WD Gold drives, made it a linux NFS share and gave it to oVirt to put VM's on 
as an NFS Domain. Just a single drive.  Migrated the disk with the fresh 
windows 10 installation to it configured as VirtIO-SCSI, and booted the vm with 
16GB ram, 8:1:1 cpu's.  To our surprise it still blew.  Just ran a winsat disk 
-drive c: for example purposes and the spice viewer repeatedly freezing, had 
the resource monitor open watching the 10,000ms disk response times with 
results...results were I rebooted because the results disappeared I didn't run 
it as administrator. And opening a command prompt is painful, the disk is still 
in use The task manager has no words on it.  Disk is writing like 1MBps. 
command prompt finally showed up and looked blank with the cursor offset with 
no words anywhere.  
So the reboot took .. Well turning off took 2 minutes. Booting took 6 minutes 
30 seconds ish.  Logging in: 1m+

So 9-10 minutes to reboot and log back in a fresh windows install. Then 2 
minutes to open a command prompt, task manager and resource monitor.
During the write test disk i/o on the vm was less than 8, from the graph looks 
like 6MBps.  Network traffic is like 20Mbps average, cpu is near zero, a couple 
spikes up to 30MBps on the disk.  I ran this same thing on my disk and it 
finished in <1m.  Ran it on the vm...still running after 30 minutes.  I'll wait 
for the results to post them here.  Ok It's been 30 minutes and it's still 
writing.  I don't see the writes in the resource monitor, windows is doing a 
bunch of random app updates or something with candy crush on a fresh install 
and, ok so I hit enter a bunch of times on the prompt and it moved down to a 
flush-seq...and now it shows up in the resource monitor doing something 
again...I just ran this on my pc and it finished in less than a minute... 
whatever it's doing it's almost running at 1MB/s

I think something went wrong because it only shows like 2 minutes passing at 
any test and then a total of 37 minutes.  And at no time did the windows 
resource graphs or any of the oVirt node system graphs show more than like 
6MB/s and definitely not 50 or 1GBps... flat out lies here.
C:\Windows\system32>winsat disk -drive c
Windows System Assessment Tool
> Running: Feature Enumeration ''
> Run Time 00:00:00.00
> Running: Storage Assessment '-drive c -ran -read'
> Run Time 00:00:12.95
> Running: Storage Assessment '-drive c -seq -read'
> Run Time 00:00:20.59
> Running: Storage Assessment '-drive c -seq -write'
> Run Time 00:02:04.56
> Run Time 00:02:04.56
> Running: Storage Assessment '-drive c -flush -seq'
> Run Time 00:01:02.75
> Running: Storage Assessment '-drive c -flush -ran'
> Run Time 00:01:50.20
> Dshow Video Encode Time                      0.00000 s
> Dshow Video Decode Time                      0.00000 s
> Media Foundation Decode Time                 0.00000 s
> Disk  Random 16.0 Read                       5.25 MB/s          5.1
> Disk  Sequential 64.0 Read                   1220.56 MB/s          8.6
> Disk  Sequential 64.0 Write                  53.61 MB/s          5.5
> Average Read Time with Sequential Writes     22.994 ms          1.9
> Latency: 95th Percentile                     85.867 ms          1.9
> Latency: Maximum                             325.666 ms          6.5
> Average Read Time with Random Writes         29.548 ms          1.9
> Total Run Time 00:37:35.55

I even ran it again and it had the exact same results.  So I'll try copying a 
file from a 1gbps network location with an ssd to this pc.  It's a 4GB CentOS7 
ISO to the desktop.  It said 20MB/s then up to 90MB/s...then it dropped after 
doing a couple gigs.  2.25 gigs to go and it's going at 2.7MB/s with some 
fluctuations up to 5MB.  So to drive this home at the same time... I copied the 
file off the same server to another server with ssd disks and it ran at 100MB/s 
which is what I'd expect over a 1gbps network.  

All this said, we do have an ssd gluster 2+1 arbiter (which seemed fastest when 
we tested different variations) on the 1TB ssd's.  I was able to do reads from 
the array inside a VM at 550MB/s which is expected for an ssd.  We did dd 
writing zero's and got about 550MB/s also from the ovirt node.  But inside a VM 
the best we get is around ~10MB/s writing. 

Basically done the same testing using windows server 2016, boot terrible, 
opening applications terrible. But with sql server running off the ssd gluster 
I can read at 550MB/s but writing is horrific somewhere around 2-10MB/s.

Latency between the nodes with ping is 100us ish.  The hardware should be able 
to do 200MB/s HDD's, 550MB/s SSD's but it doesn't. And it's evident in every 
writing scenario inside a vm.  Migrating VM's is also at this speed.
Gluster healing seems to run faster, we've seen it conusme 7-9 Gbps.  So I feel 
this is an oVirt issue and not gluster. Especially since all the tests above 
are the same when using an NFS mount on the box running the VM in oVirt.

Please guide me. I can post pictures and such if needed, logs whatever. Just 
ask.
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