How to fix Avast Antivirus High CPU Usage

Discussion in 'Security and Anti-Virus Software' started by Ultra Male, Mar 2, 2016.

  1. Ethrem

    Ethrem Notebook Prophet

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    Turn off Avast's option to run heuristic analysis... A) it results in false positives and b) it deep scans everything in the machine... Heuristic analysis is a joke from any company except panda cloud because it chews through CPU looking for embedded virus signatures... They're so incredibly rare that 90ish percent are false positives because virus makers know how to change signatures. It's an old throwback from Windows 3.1 and DOS when the makers of the virus weren't smart enough to flip a couple bits and shuffle the program around to change the code but still have the same effect... Its useless and on first install it will run on second boot... Eats between 1 and 2 cores plus between 10 and 50MB/s of read speed from your hard drive.
     
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  2. Woodking

    Woodking Notebook Evangelist

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    I've been using Avast for years and it's worked really well for me on multiple machines (free version registered) but recently - last couple of weeks from memeory - it has made my day to day machine quite slow after it updated. I don't get the high CPU usage mentioned on here but pages were taking quite some time to load and it reminded me of the old US Robotics 56k modem days! WU is disabled but the machine is up to date and no telemetry and a Hosts file with the usual suspects blocked.

    After reading this thread I checked the settings mentioned by Phoenix in Mail Sheild/Customise/Enable HTTPS Scanning and I disabled it to test (but left the others as they were) and this made an instant difference to browsing etc after rebooting the machine.

    I use Google.co.uk as a home page (with FireFox latest) and as that is HTTPS by default I guess this could be the root of my issue as nothing else has changed on this machine and its a good spec.

    Any issues leaving this scanning switched off, I'm a careful user and don't go onto any 'suspect' sites?
     
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  3. Ultra Male

    Ultra Male Super Tweaker

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    @downloads @Ethrem @Mr. Fox @toughasnails @Papusan @hmscott

    New observation, without changing any of the default avast settings, Today I installed it again and ran wPRIME on 8 threads/4 cores......

    My 32M benchmark got worse....

    before avast = 4.65 s

    after avast = 5 s

    what I realized is, when I launch wPRIME, it takes a bit longer to start than usual, so that lead me to think that Avast may be scanning it or something....

    Next, I added it to the exclusions of avast and ran it....

    first sign was good, wPRIME launched much faster just like before I installed avast.....

    then I ran the benchmark again and here are the results.....

    NEW.png
     
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  4. Ethrem

    Ethrem Notebook Prophet

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    Not really surprising. I always disable all shields for 10 minutes when I'm benchmarking because avast monitors everything from unusual CPU usage to RAM and everything inbetween.
     
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  5. G.E. Hoostal

    G.E. Hoostal Newbie

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    Thanks. I tried it & it helped.
     
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  6. Ultra Male

    Ultra Male Super Tweaker

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    you're welcome.
     
  7. Freonpsandoz

    Freonpsandoz Newbie

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    My computer became completely unresponsive after running uTorrent for a significant time, even when not downloading anything. I couldn't close apps or restart. It took several tries for it to even respond to the power button. Disabling intelligent stream scanning seems to have fixed the problem for me. One of the problems with the makers of security software is that they actually believe it is more important for a computer to be completely secure than for it to be usable.
     
  8. Ultra Male

    Ultra Male Super Tweaker

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    uTorrent IS a virus! Other than the fact that is has OpenCandy spyware bundled and hidden within it and the annoying toolbars and PUPs (potentially unwanted programs), the last time I tried it which was about 8 months ago, after using it for a while the following 2 things happened:

    1) PresentationFontCache.exe started having abnormally high CPU usage causing my laptop's fans to continuously spin

    2) After I reboot, it wouldn't log in to my account but rather it would say "Preparing Account" and eventually logs in to a temporary account as uTorrent has completely wiped my user account!

    Due yourself a favor, uninstall uTorrent using GeekUninstaller and to get rid of all the remnants and start using uTorrent unless you want to bid farewell to your computer soon.
     
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  9. Freonpsandoz

    Freonpsandoz Newbie

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    I don't have OpenCandy or any other PUPs on any of my computers. Is it possible you downloaded uTorrent from somewhere other than utorrent.com? Some download sites repackage popular freeware with their own installer and add PUPs.
     
  10. Ultra Male

    Ultra Male Super Tweaker

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    Nope downloaded straight from uTorrent. This is not new it’s been like this since uYorrent v3. Use it at your own risk, one day you will remember me
     
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