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breacH
Contributor
Contributor

Slow transfer rate between datastores (copy or move)

Hello,

I just did a fresh install of ESXI 6.7 on my home lab server. (i7 2600 on intel motherboard)
The VMs are running fine, all stored on SSD.

I wanted to make a backup of the VMs from the SSD on a WD 1TB drive and the transfer is extremely slow.
For example, a Windows 10 VM thin provisioned that use actually about 30 GB took more than 2 hours.
I did the copy with the datastore management.

Is that any normal?

I remember on ESXI 5.5 the transfer was way more quicker.

Exact setup is:
- intel i7 2600
- motherboard intel DZ77GA-70K

- Samsung 860 EVO SSD and WD Blue 1To (both VMFS 6)
- Both drives connected to the same sata controller (intel one)

Thanks a lot for the help, and have a nice day!

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6 Replies
bhuqwl
Contributor
Contributor

Have you tried a smaller VM? Are average transmission rates all slow?

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breacH
Contributor
Contributor

Thanks for your reply.

Yes, all transfer are slow between datastores, whatever the VM's size.

But i noticed that uploading or download on datastores from desktop PC is good (~110MB/s)
Makes it even stranger..

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breacH
Contributor
Contributor

Hello,

A little bump of this thread..

I saw in the vmk warning log something like:
"ScsiDeviceIO: 1199: bla bla sata device :Deviceperformance has deteriorated. I/O latency increased value etc"

This line repeats several times with latency always bigger, and then:

"NMP: nmp_DeviceRequestFastDeviceProbe:237: NMP device bla bla sata device state in doubt; requested fast path state update..."

I dont know if this could be related to my problem.

I also read that the native vmw_ahci driver sometimes causes problems.

Should i switch to the legacy linux driver?

I'm a bit afraid to make this move...

Thanks again for your replies!

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breacH
Contributor
Contributor

Hi,

Thread bump again..

Just to say that i tried to disable the native esxi driver and let the legacy one to load.

No change in speed in datastore or between datastores.

I give up on this

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wila
Immortal
Immortal

Hi,

Not exactly sure what this means:

I did the copy with the datastore management.

But FWIW, after reading this thread I suspect that the WD Blue disk is not performing well in your config.

--

Wil

| Author of Vimalin. The virtual machine Backup app for VMware Fusion, VMware Workstation and Player |
| More info at vimalin.com | Twitter @wilva
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breacH
Contributor
Contributor

Hi,

Sorry for late answer..

I meant to copy file with the datastore's files manager. The one on the web interface.

The WD Blue disk is old but functionnal. No SMART error or anything.

I did installed GhettoVCB and made a script to backup all the VM.
With GhettoVCB it copy at a constant 96MB/s which is pretty good.

I think that when i do copy VM with the datastore's file manager, the system inflates VMDK files, hence the slow rate and long time copy.

Thanks again for your replies and have a nice day!

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