You've probably heard the recommendation to keep only one antivirus on your computer. What is the reason? Is this advice based on technical background? Or is this just an attempt by marketers to dissuade you from buying competitive software?
Indeed, some security software developers do their best to convince customers to buy several anti-virus solutions from their company at once, but this is not the reason why you should not run two antiviruses.
Chain reaction: endless scanning.
This problem was acute in the early years of anti-virus software development, but it is worth mentioning now. The first anti-virus programs scanned all files that the computer accessed during operation.
In general terms, it looked like this: the operating system let the antivirus know that the file was being read, and the scan was started. This action also triggered the second antivirus, if it was installed. At the same time, the operating system sent another signal to the first anti-virus about a new call to the file. The process was closed. As a result, both antivirus products scanned the same file in turn until they completely clogged the computer's memory and it became impossible to work on it.
As of today, the problem has been largely resolved. Modern high-quality programs no longer scan a file every time it is accessed. This allows you to economically use computer resources while maintaining a high level of protection.
Technical complexity: potential software incompatibility.
Modern antivirus software is like a barrier between the operating system and the programs that run on it. The development of security software is not an easy process; it requires a great deal of experience from a specialist, since a huge number of variables must be taken into account when writing antivirus code. Security programs are created in many different ways, and developers often deviate from the recommended coding standards. In particular, they use undocumented interfaces of operating systems, which can lead to crashes and freezes during use.
Some developers simply do not have enough knowledge to create such a product that will be fully compatible with all possible programs. Some people just don't give a damn how users will deal with software conflicts. For the same reason, you should not skimp on antivirus protection: a reliable vendor will not leave their product unsupported and will release a patch that fixes the failure in time.
Priority issue: who will quarantine the file?
Imagine that you have two antivirus products installed and both scan your system in real time. You run a dangerous file and receive two simultaneous threat messages. Which program will take priority in this case is unclear. If one of them quarantines the infection, you will receive new error messages, since the second program will lose the suspicious file. At best, you just get confused about which file is infected, who scanned it, where it was moved, etc. In the worst case, none of the antiviruses will be able to move the file to quarantine, and your computer will remain defenseless against the virus.
Allocating resources: bigger is not always better.
Running two antiviruses is not worth it, if only because it will lead to increased load on the computer (especially on the RAM). The growing number of threats invariably leads to the complexity of security programs, and the computer has to spend more and more resources on their work.
Thus, you can sacrifice 1-2 GB of RAM in order to increase the probability of detecting a virus from 98% to 99%, but is it worth it? Each file on the computer must go through the algorithms for checking all running antiviruses. To do this, a huge amount of code will be run. This will take away CPU and memory resources that you could use for other tasks.
So the best option is undoubtedly to use one comprehensive solution from one developer. With this approach, you will provide your computer with multi-layered protection, eliminate potential conflicts between programs and not face slow system performance.
The Topic of Article: Why can't I run two antiviruses at the same time?.