MSE high CPU usage

I have noticed that when MsMpEng starts up, an svchost starts up and runs at 50% - it continues to run until MSE finishes its download and daily scan. My system spikes to 100% , especially if I am doing other work at the time. I have MBAM set to download and scan 1 hour after MSE so there is no clash there. My system has very low CPU usage on average - until MSE starts up. There is a setting in MSE 'limit CPU usage during scan' set at 50% - I thought that this meant that MSE would not start a scan if my CPU usage was 50% or above - so I have no need to change this, right?

I have not seen this on W10, it is only happening on W7. Anyone else see this svshost at 50% CPU when running MSE ?

 

This very situation is why I cannot understand why people think this is a light product. The only way I have ever been able to prevent this is to disable it and install something else.

 

I don't recall the CPU usage when using MSE, but I DO recall the huge slow down of my Win 7 system when it was installed, which is why I uninstalled it and started using something else.

 

That MSE feature cut down the impact that a scan has on the system. The amount of CPU time allocated to the scan can be limited. Basically, 50% means half-throttle for scanning so it'll take longer to complete but not consume all of the systems resources that could be a necessity for multitaskers.

 

The problem with that 50% is that with a multicore CPU it uses 100% of half of the cores. That will still choke most any machine.

 

I have that KB installed. I thought KB312810 was only associated with windows update - re: faster delivery of updates on Patch Tuesday. I know that MSE def updates are delivered thru WU but they are very small in size and get downloaded very quickly - I see no delay at all. I am not seeing what you are seeing in CPU usage.

 

You're comparing MSE on Win7 vs Defender on Win10 which is what most people refer to these days. Different products, yet referred to with the same name.