Why ULAV is killing my IS


I have this eeePC with 900 Mhz Celeron running Win 10 and FS - IS installed on it. I do not use it daily, but a couple of times a month.

My problem is that when I turn it on updates are killing it.

If there are uninstalled Windows updates available, downloading and installing takes all CPU and disc access. However, eventually it get updated and there are not always new updates.


The other updates are FS IS updates Those are available mor frequently and they, too, are killing it



This is after the CPU has leveled, but the nothing can be done because ULAV is using disc access.


I've installed IS so at first I wondered why is ULAV there in the first place.

According to

‎20-06-2017 03:45 PM
Re: What happened to ULAV?

Hello  ! Ultralight engine is now the core of FS AV, ulav not intended to become a GP AV.


ULAV is part of IS now, so it is OK that I see it, but it does not help with the performance.


Still would like to know if my installation is OK.

Secondly can I do something about it other  than just having the eeePC on daily even if I do not need to use it? Eventually after a day to two the performance is not reduced by the updates anymore.

An option could be the use of aother  lighter cloud based AV like Immunet, but would that give less protection?


I do have ULAV on other PC's, but I use them daily and they are faster so I do not see such a performce problem  with them.



  • martink
    martink Posts: 435 Influencer

    Thanks  https://community.f-secure.com/t5/user/viewprofilepage/user-id/23391
    If I have it on once in 1 - 3 weeks it appears that there are always FS and MS updates to downloaded and installed and I just have to live with that and have the eeePC up more frequently and allow time for the updates.


    Screenshot (6).png

    These are the updates which were installed during the time of limited response.

    This week without network connection the CPU looks like this

    Screenshot (5).png

    After 10 - 15 minutes that levels at

    Screenshot (7).png

    After connect to LAN the updates started again

    Screenshot (13).png

    The FS updates were already installed at that point

    Screenshot (9).png


    With the faster PC with the real ULAV the Microsoft modules installer can also have a high CPU value, but that does not last as long. A bigger problem is that when the PC is on for a day or more Firefox and Thunderbird CPU can be more than 50 % each at times. Fortunately restart of the program solves that for another day.



  • martink
    martink Posts: 435 Influencer

    Apparently one contributing factor is that this particular PC is single chore sing thread. On another slow PC the updates only take 50 % of the CPU which is 2 core.

  • nanonyme
    nanonyme Posts: 145 Path Finder


    Just to expand on Ukko's answer: not only is F-Secure Ultralight AV a different thing than the Ultralight core running inside F-Secure SAFE/Internet Security, the two are also incompatible. If you manage to install them on the same machine (by somehow managing to install the beta Ultralight AV product on a machine with a regular F-Secure AV product), there is likely to be conflicts and the setup may break. The installers are supposed to detect that they conflict with each other and uninstall each other.

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