12.1.34.0 + Windows 1809 = Extreme upload speed degradation bug

[rawalanche 2]

Hello,

for the past few days, after my Windows received update to 1809, I've wasted countless hours of troubleshooting why are my upload speeds to certain servers incredibly slow. Based on the speed measurements, the upload speeds were capped at about 128kb/s. The upload speeds were capped only on some specific servers, not all of them, which made the issue that much harder to trace.

I've wasted not only my time, but also time of Google One support team and my ISP tech support. In the end, when I was completely hopeless, I wanted to make once more sure the issue was not on my end device, and sure enough, ESET Internet Security was the culprit. 

After 1809 Windows 10 update, upload speeds to some, but not all servers were severely affected. It was only about 10% of the servers, however they were some important one, such as Google Servers responsible for receiving Google Drive data or uploads to YouTube. 

Here is an example of one server affected, a NFX SpeedTest server based in Prague. 3 separate speed tests ran minute apart:

After that, I've uninstalled ESET Internet Security, and ran the tests again:

When I restarted the PC, and reinstalled ESET Internet Security, this is what I got again:

It appears that it may have something to do with ESET interfering with the TCP Receive Auto-Tuning: https://support.microsoft.com/en-us/help/4494445/tcp-receive-auto-tuning-level-feature-in-windows since as part of the troubleshooting process, disabling TCP Receive Auto-Tuning using netsh interface tcp set global autotuninglevel=disabled command did improve the issue a bit. The upload speed still wasn't nearly where it's supposed to be, but it improved from about 0.2Mbps to 2.0Mbps.

I hope this can be resolved ASAP as I can not afford to leave my PC unprotected, but at the same time I can not afford to not be able to upload backups and work related files.

Thank you.

[Marcos 5,074]

Does switching to pre-release updates in the advanced setup and downloading the latest modules make a difference?

If possible, try temporarily uninstalling EIS and installing ESET NOD32 Antivirus. It would be valuable for us to know if that makes a difference in terms of the network speed or not.

[rawalanche 2]

Hello,

so update to latest modules did not solve the problem, however switching to the pre-release update channel did. Is there any possible instability/known issues when running the pre-release version? Also, could it be possible to find out what was the cause of this behavior? Which particular network bandwidth related bug was introduced in 12.1.34.0 and is already fixed in the pre-release channel?

[Marcos 5,074]

The issue is not related to v12. What fixed it was an overhaul of a several years old code in the firewall module.

Modules on pre-release update servers are typically those that are later released for all users since not many users update from the pre-release channel. We generally recommend using pre-release updates for technically savvy users on non-critical systems. I for one can hardly remember severe issues caused by using modules from the pre-release channel. By using the pre-release channel, you get early access to fixes and improvements with the possibility to switch to regular updates in case of an issue which is not possible when using regular updates.

[rawalanche 2]

2 minutes ago, Marcos said:

The issue is not related to v12. What fixed it was an overhaul of a several years old code in the firewall module.

I am not sure about this. I've started to encounter the issue only about 4-5 days ago. I'd notice otherwise, since I backup data on Google Drive almost every day. It's definitely not happening for several years.

Edited April 19, 2019 by rawalanche

[Marcos 5,074]

10 minutes ago, rawalanche said:

I am not sure about this. I've started to encounter the issue only about 4-5 days ago. I'd notice otherwise, since I backup data on Google Drive almost every day. It's definitely not happening for several years.

We know but that was a very old code that had to be rewritten. Probably recent Windows updates have caused the issue to manifest since users hadn't reported it until recently.

[rawalanche 2]

Alright. Hopefully it won't happen again. Non the less, I am on the non-targeted Windows Update channel, so I receive updates half a year after others. 1809 has been out for at least 5 months now. Very curious no one has reported it before.

[itman 1,659]

I am running Win 10 x(64) 1809 fully patched w/ EIS 12.1.34.

I enabled pre-release updating to resolve the erroneous invalid Ethernet packet IDS detection issue which may or may not be also related to this speed issue.

My speed tests are downright strange. The speedtest.net test shows a download speed of 26 Mbps and an upload speed of 33.45 Mbps - err, what? Verifying the previous test results, I tried my ISP, AT&T, speed test. The download speed was approximately the same but the upload speed was 43.4 Mbps - err, double what?

I have never seen upload speeds like this; especially exceeding download speeds.