Avast webshield slows down internet speed

General Topics
1

Hi,

Since Avast 7.0.1474 my internet download speed dropped from 75-80Mbit/s to 15-20Mbit/s.
Updates 8.0.1482 and 8.0.1483 didn’t cure the problem.

When I disable webshield the speed is 75-80Mbit/s again.
Before 7.0.1474 it was also 75-80Mbit/s with webshield on.

The odd thing is that it’s only on my Windows XP SP3 pc, my Windows 7 laptop (also with avast) doesn’t have this problem. The win7 laptop has wireless 40-65Mbit/s and on lan 75-80Mbit/s no matter if webshield is on or off.

-I have reset Avast to factory defaults;
-I uninstalled Avast with aswclear.exe, downloaded again and reinstalled;
Both didn’t fix the problem.

I tested the speed with Firefox, IE and Google Chrome on multiple speedtest-sites.
All came up with simular results.

My browsers are up to date, as are flash, java and other software.

I am at a loss what could cause this and hope someone here has an idea.

2

try a different way to measure the speed…

download a big file, like xp service pack3… time the download
then turn off shield and do it again… what is the time…and how big is the time difference?

3

I dll the sp3 306MB file twice with webshield on and twice with webshield off
It didn’t make any difference all downloaded in little less than 3 min.

FF reported dll speeds of 1.8MB/s to 2.8MB/s during download (so 14.4Mbit/s to 22.4Mbit/s).

4
I dll the sp3 306MB file twice with webshield on and twice with webshield off It didn't make any difference all downloaded in little less than 3 min.
so just the webshield that is fooling those online speedtests. ;)

i had the same issue with Malwarebytes and they told me to try the download test

5

That might not be the case, it could also be that upload speeds from the MS server to my pc are not faster than
15-20Mbit/s and that at those speeds there is no problem with avast webshield.

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EDIT:

I just noticed a funny thing during all this testing.

After turning all shields off and on again 5 times the speedtests give 80Mbit/s download.
Downloading the XP SP3 file then takes 1 min 40 sec (so around 3MB/s or 24Mbit/s)

Restarted pc: back to the old results, disable/enable shields 5x: speedtests 80Mbit/s download and xp sp3 file download almost twice as fast.

6
Restarted pc: back to the old results, disable/enable shields 5x: speedtests 80Mbit/s download and xp sp3 file download almost twice as fast.
mysterious. ???