SMB Slow Speeds

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I dont know how you guys get good SMB copy speeds over the network

i have the issue with my HP gen 8 xeon on esxi 6.5 SATA setup (no scsi raid), with synology 5.2 , 6.1 1.02 , 6.1 1.02a

so all versions in fact :smile:


what happens, i do a clean install, just setup 1 shared folder

so i start copying from my laptop over 1 gb network to synology, transfer speeds are looking verry good, arround 110 MB/sec , then after a miniute or something, the speed drops to like 8-9 MB and is verry slow and constant drops (tested with a file of 5-10 GB)


PS: dont have issues when running in bare metal


here below some screens of my setup

doesnt mather if i add more/less processors/memory, also tried SATA controller/SCSI controller

what am i missing to get good SMB speeds?




screens see attached



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Have you recently upgraded to ESXI 6.5?


Once i upgraded I had terrible hard disk speeds, ESXI kept crashing and Xpenology lost my disk configuration every time I rebooted it.


I found out that ESXI 6.5 uses a new storage driver which can cause speed problems. Once disabled and it reverted back to the old default driver everything worked fine.


See this article to check: ... i.html?m=1


Hope this helps?

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ok, gonna try it out


what esxi version you used before? because i see in that link you posted a reply :



I'm experienced low write performance on my SSD disk (50-120MB/s) under ESXI 6.5. First I disable vmw_ahci but transfer was more/less the same, Also I did revert ESXI to 6.0 u2 but again the same.

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