[SOLVED] How do open tabs affect game performance if you have plenty of RAM?

[ShangWang]

If you had plenty of RAM and was playing a game with a lot of tabs, would you still get some performance reduction if you're not running out of RAM? Would closing tabs still increase performance in any way if you're not running out of resources?

Tabs do take up CPU resources, but is it not as much as RAM resources and would it make much of a difference in performance if the game does not use close to 100% CPU?

Does performance drop if CPU usage is at 90%+, and would open tabs affect that somehow? What factors indicate how much CPU % is used, and do most games take up a significant percentage and why?

 

[Eximo]

A complicated topic, with several answers.

In general, yes, closing tabs will increase performance. Modern browsers do a pretty good job of parking resources when not in use, but excessive tabs will keep the memory occupied. Windows can, and does, take some data in memory that isn't likely to be needed immediately and will store it in the swap file, further increasing available system memory.

Not really sure what you mean by does performance drop if the CPU is at 90%. If it is at 90%, then it is mostly utilized with little room for further processing. At that point all cores would be in some level of use and switching between tasks takes time as different data is required to be processed.

Most games do not utilize a system's full CPU resources. They can if the CPU is particularly slow or lacks multiple cores though. Older games were compiled for single core computers, and even today games rely on a single main thread running on one CPU core, so while that one core is utilized as much as possible, the other cores can do other things.

Multitasking though is sort of a myth, it seems that way to us, but a CPU really can only do one thing at once. This further extends to cores, each core can really only do one thing at a time. Or in the case of hyperthreading/SMT, you can task a CPU to do multiple things, but then it is committed to completing both tasks. We see simultaneous processing by the CPU actually switching tasks in and out repeatedly. The more tasks you have running at the same time, the more often this happens.

Schedulers, branch predictors, etc are all affected by having programs running in the background as well.

 

[ShangWang]

Not really sure what you mean by does performance drop if the CPU is at 90%. If it is at 90%, then it is mostly utilized with little room for further processing. At that point all cores would be in some level of use and switching between tasks takes time as different data is required to be processed.

I mean the % use in task manager, I was wondering if it being high means processes will slow down in general, or will just not be able to do more tasks. Would it "kill" programs like it does when RAM is full and using up the utilization % doesn't necessarily mean performance will drop?

To confirm when a game is CPU intensive, it utilizes more "clocks" to run optimally, but does that relate to utilization % all the time? What other factors contribute to CPU % utilization?

 

[Eximo]

Well, that depends on other factors. All things being equal a task that takes 8% of the CPU should run just as fast on an idle CPU as one that is running at 90%. But as I mentioned there will be some overhead for each running application so in practice it would be a little slower.

A CPU running at 90% is also going to be hot, unless it is at a fixed clock ratio it would perform the job faster when it is cooler, since it would then run at a higher clock speed.

When you exceed a CPUs total processing capability, it will still do the tasks, just take longer to do them, yes.

That last is actually a good question that I am not sure there is a clear answer for. Likely depends on the OS in question. However, it would generally be some count of the total passage of time against available processing capacity. So if the CPU can do 1 billion calculations per second, and you do 100 million in that second, you would be at 10%. Apparently Windows does this by running an idle task when the CPU is not called for. A direct ratio of not idle/idle is used for each core.

 

[ShangWang]

When you exceed a CPUs total processing capability, it will still do the tasks, just take longer to do them, yes.

I see, so technically apps would never "crash" but just take a long time to process? I'm guessing this contributes to programs showing the hazed screen and "not responding" so even if apps don't crash, they will probably never load/respond?

That last is actually a good question that I am not sure there is a clear answer for. Likely depends on the OS in question. However, it would generally be some count of the total passage of time against available processing capacity. So if the CPU can do 1 billion calculations per second, and you do 100 million in that second, you would be at 10%. Apparently Windows does this by running an idle task when the CPU is not called for. A direct ratio of not idle/idle is used for each core.

I see, interesting thanks! I think clock utilization would probably go hand in hand with CPU % utilization, but that's all I can guess. More CPU intensive program/CPU calculations needed to run the program = more % utilization most of the time I suppose.

 

[Eximo]

I see, so technically apps would never "crash" but just take a long time to process? I'm guessing this contributes to programs showing the hazed screen and "not responding" so even if apps don't crash, they will probably never load/respond?

Well, that depends on what is causing the 100% utilization. If it is just doing too many things at once, it should eventually get it done. (Like when my laptop decides to run an AV scan at the same time as I am attending video conference, it just does both jobs really slowly, priority to the video call)

If an application is causing excessive CPU usage due to an error, then it could spend forever on it without external intervention.

 

[ShangWang]

Well, that depends on what is causing the 100% utilization. If it is just doing too many things at once, it should eventually get it done. (Like when my laptop decides to run an AV scan at the same time as I am attending video conference, it just does both jobs really slowly, priority to the video call)

If an application is causing excessive CPU usage due to an error, then it could spend forever on it without external intervention.

To clarify I mean if you had multiple apps that running them by themselves would contribute to over 100% CPU usage. They are constantly utilizing the %. Would the few apps that are trying to start up/run new processes just crash or not work/never open because there is never enough room to utilize?

Also just to confirm again a game that requires lots of CPU utilization/clock cycles will slow down because it cannot access the "full clock cycles" that it wants and more because if for example a browser is using some of those clock cycles, it therefore has to share and reduces the amount of performance it can possibly get?

 

[Eximo]

To clarify I mean if you had multiple apps that running them by themselves would contribute to over 100% CPU usage. They are constantly utilizing the %. Would the few apps that are trying to start up/run new processes just crash or not work/never open because there is never enough room to utilize?

Also just to confirm again a game that requires lots of CPU utilization/clock cycles will slow down because it cannot access the "full clock cycles" that it wants and more because if for example a browser is using some of those clock cycles, it therefore has to share and reduces the amount of performance it can possibly get?

CPUs operate on interrupts, so there should always be a way to get the CPUs attention. If a new task comes in, it will get assigned processing time when possible. Now of course when you are at 100% that also means your interface to the computer may be quite slow, so there is that. But they shouldn't crash, they may appear to hang for a while. I often run into such scenarios with my little dual core laptop and my atom based Lenovo ThinkStick. Just takes a while for things to get going.

Yes, in that scenario the game engine is slowing down because the CPU has to stop, bring in data for that task, and process it before resuming work on the game engine. That is an oversimplification, but is more or less correct in principle.

And the same is true if the CPU is at 100%, the game could run faster, but the engine has to wait on the CPU to finish processing what it is doing.

 

[ShangWang]

CPUs operate on interrupts, so there should always be a way to get the CPUs attention. If a new task comes in, it will get assigned processing time when possible. Now of course when you are at 100% that also means your interface to the computer may be quite slow, so there is that. But they shouldn't crash, they may appear to hang for a while. I often run into such scenarios with my little dual core laptop and my atom based Lenovo ThinkStick. Just takes a while for things to get going.

Yes, in that scenario the game engine is slowing down because the CPU has to stop, bring in data for that task, and process it before resuming work on the game engine. That is an oversimplification, but is more or less correct in principle.

And the same is true if the CPU is at 100%, the game could run faster, but the engine has to wait on the CPU to finish processing what it is doing.

Sounds good, thanks! So in terms of CPU % and clock cycle utilization, I'm understanding that the game will slow down from a combination of constant processes that need to use CPU resources, but also new processes.

I think I get the general idea but to be more specific the CPU is always going back and forth between if you had even a single chrome tab and the game to utilize the CPU resources, and no matter if that chrome tab is doing absolutely nothing, it still has to go back and forth to bring data and therefore slows down performance by some degree unless the game did not require those additional resources?

Slowing down would ONLY apply if the game could utilize more clock cycles than the the CPU provides?

 

[Eximo]

Sounds good, thanks! So in terms of CPU % and clock cycle utilization, I'm understanding that the game will slow down from a combination of constant processes that need to use CPU resources, but also new processes.

I think I get the general idea but to be more specific the CPU is always going back and forth between if you had even a single chrome tab and the game to utilize the CPU resources, and no matter if that chrome tab is doing absolutely nothing, it still has to go back and forth to bring data and therefore slows down performance by some degree unless the game did not require those additional resources?

Slowing down would ONLY apply if the game could utilize more clock cycles than the the CPU provides?

Yes, also including the operating system's processes.

Modern processor schedulers do a pretty good job of keeping things separate if possible. If one core is running the main game thread, and other game functions on other threads, that does still leave room to maintain an idle condition on another application without much interference to the game. But it is all a matter of scale. If it takes a few extra clock cycles, you aren't likely to notice (that being in the ns second scale)

Still, if the application is running, even just sitting idle, it is still doing things. It is checking for user input, it might be running its own memory clean up routines, it may wake up every ms, check what is happening, resume idle, just depends what the core process is actually designed to do.

Not sure we can apply such an absolute. But I think that mostly holds true. That same system with more resources and the same clock cycles might be able to move a bit quicker. But if we are assuming a static system that sounds right.

 

[Bob.B]

If you had plenty of RAM and was playing a game with a lot of tabs, would you still get some performance reduction if you're not running out of RAM? Would closing tabs still increase performance in any way if you're not running out of resources?

Tabs do take up CPU resources, but is it not as much as RAM resources and would it make much of a difference in performance if the game does not use close to 100% CPU?

Does performance drop if CPU usage is at 90%+, and would open tabs affect that somehow? What factors indicate how much CPU % is used, and do most games take up a significant percentage and why?

I look at it the simple way.
Everything that's running or even loaded takes something from the machine.
Since the machine only has so much something to work with there will be an impact some place for everything that is running or even loaded.

 

[USAFRet]

There are tabs, and then there are tabs.

A couple of browser tabs with static text is much less resource intensive than a couple of dozen of them all playing individual utube videos.

 

[hotaru.hino]

Does performance drop if CPU usage is at 90%+, and would open tabs affect that somehow? What factors indicate how much CPU % is used, and do most games take up a significant percentage and why?

CPU % utilization is simply a measure of how often it spent not running the "System Idle Process." That's it. You can't glean from this value how much of the CPU is actually being used. See https://www.howtogeek.com/411569/what-is-system-idle-process-and-why-is-it-using-so-much-cpu/

 

[Karadjgne]

Task Manager itself is somewhat misleading. If you see 90%, on a 6 core cpu, count on a couple cores at least being at 100%, meaning they might as well not exist because no further computation can be done on them. So in reality you'd be looking at 4 cores or less with roughly less than 10% available resources per core. That's going to be slower in general than having 4 cores at 100% with the remaining 2 cores around 70% to get the 90% average, as said above most stuff being highly single threaded you've got 2 cores with around 30% space to maneuver.

So take TM with a grain of salt, it being a single number representing workload across All the cores. The number itself isn't all that important, it's what the number represents that is.