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Re: Windows users! Help us test upload performance tuning?

From: Daniel Jeliński <>
Date: Mon, 6 Aug 2018 13:47:02 +0200

2018-08-05 10:01 GMT+02:00 Andy Pont <>:
> VirtualBox 5.0.16 was released in March 2016 and so it two years out of date
> and is unsupported by Oracle. The current version is 5.2.16. If possible
> you should try upgrading and seeing if you get the same results.

Ok, so I installed Win 10 on Virtualbox 5.2.16 on my machine and I can
confirm Jan's findings; in NAT mode the ideal backlog stays flat at 64
KB, and the patch provides no benefits.
Once I switched to "Bridged adapter", I got normal results (as in,
similar to what other people reported):

Microsoft Windows [Version 10.0.17134.112]
generating test file...
running vanilla...
start:0.687000 total:6.062000
running patched...
start:0.625000 total:2.407000

Looks like a limitation of VirtualBox's NAT mode.
Received on 2018-08-06