Cis completely takes over the CPU, work is impossible


every few days CIS completely takes over the CPU and RAM. There is no way to work on the computer, even watching a movie does not work. I have to save all my files and restart the computer.

Please help me to turn of this behavior. If there is something big to cache or update CIS should ask, if i can interrupt my work at the time, or when it should ask again. Just to take over the computer is very unprofessional.


This should not be happening. Something is definitely going wrong.

The next time this happens please open task manager and make a screenshot of the CPU and memory being used by Comodo Internet Security at that time.

Also, for how long does this last and is there a patter as to when it happens? For example, does it always happen when you are running a particular program, etc…?


It seems to happen when CIS downloads and installs new virus signatures.

I disabled the option ‘look for new signatures’ and ‘look for new software updates’ but CIS does not care and updates and installs new signatures anyway.

Software that calls home without permission is a irreparable breach of trust. i will remove CIS becouse of this.

Here is the screenshot, you asked for.

(Ram usage rises too, but later)


That’s strange. Which version of CIS do you have installed?

Also, was there a scan running at the time you took that screenshot, or was it just installing AV updates?


Version: 6.3.297838.2953

I did not start a scan. Is there a way to really prevent all automatic updates?

Did you disable the box for “Check for database updates every…”?

Also, have you disabled the scheduled scans?

In addition, please list all other anti-malware software and maintenance software currently installed on your computer.



yes i disabled following checkboxes weeks ago:

The checkbox about software updates is grayed out. How can i disable it?

but as you can see, the signature-updates has been made 11 hours ago. (at exactly the time, the CPU was blocked):

Scheduled scans were not disabled, but i think there was no scan, since i did not notice it on the main CIS interface at the time CPU was blocked. I think the performance problem was the installation of new signatures in the background, but i will disable the scheduled scans too.

I do not use another antimalware-software. The computer is nearly clean of additional software. Only Windows XP + Firefox, Thunderbird and Media Player Classic (all as Portable-Versions)


The box for software updates is grayed out because the option above is already disabled. Thus, it is disabled as well.

Please disable the scheduled scans, just to rule out any possibility of this being what caused the update. Then, if the AV updates again without you explicitly doing it, I think it would be worth creating a bug report for this. I can’t think of why it would update with that checkbox unchecked.

Also, did there used to be any other anti-malware software which used to be installed but is now removed?


Its a clean Windows install. No other software was used.

Thanks for your help! No more questions :slight_smile:

I’m a new CIS Premium user and also encounter this problem. System is an up-to-date new-install XP in a VBox 4.3 VM assigned 768MB memory and one CPU on a OS X Macbook host. CIS is v7, auto-updated from a v6.3 install, just a few UI settings changed, others unchanged from defaults.

System was allowed to auto-update database after a boot, usually after a few minutes. CIS update window says signature install stays at 90% for a long time, well over a minute. During this time, the cavwp.exe process CPU and memory cycles up and down several times. On one cycle it’s up to nearly 500MB (out of 768) memory usage and over 80% CPU, other cycles usually max about 300MB, also 80-90% CPU. After about four or five cycles it finally dies down and the signature install is complete.

Hope this can be replicated and solved.

Initialization of bases begins with 90% after loading of updating of bases.
At Initialization a bases of the CPU gives big % loading.
But not there is a lot of as at you, at least in old versions.
I believe that at you it is connected with a caching option.
Try it to disconnect - Run cache builder

Edit: I looked at 5 versions.
CPU From 30 - 70% ( Initialization of bases )

Thanks. I disabled the idle cache builder, forced an update, but got the same result. Cycles of up to 500MB memory and 90% CPU in cavwp.exe. That makes sense as the idle cache builder is only active when idle, and a database initialization is not idle.

Suggest you re-create the VM XP system described above. Lots of XP customers may come your way for single-source combined AV and FW after MS ends XP support, so it may be worth your while to do so. That’s why I’m looking at it.

I hope it 's not something simple like resorting a combination of two already sorted lists, instead of sequentially going through both lists to create the sorted combination. That O(N) rather than O(N*log(N)), or worse O(N^2).

Thanks again.

Does this happen even if you reinstall by following the methods I advise in this topic? If so, please create a new bug report for this.