For most gamers the meaning of RAM comes down to “memory” and we all know that more RAM more better. But why do you need 4, 8, 12 or 16 GB of RAM? Does RAM even affect a game’s performance and if so how and why?
Your Answer Upfront:
More RAM allows your phone or tablet to keep more apps ready to be used. This leads to less copy and move operations needed to load your game’s assets (textures, models, sound, code) from the phone’s storage to your phone’s memory in order to be used by your game and app. If not enough RAM is available your game’s performance will decrease as assets are loaded and unloaded from memory which can also lead to your apps and games crashing.
In this article we’ll talk about RAM, explain what it is, how it works and how it affects your phone’s or game’s performance through simple to understand analogies.
What is RAM?
RAM is short for Random Access Memory and it’s a type of memory used in computers and mobile computers and tablets. The best way to explain this concept is via a small analogy.
Think of RAM as a storage cabinet under your desk while normal storage memory is your basement. If your phone runs out of battery you need to charge it, where would you find the charging cable for your phone? Down in the basement or in the storage cabinet under your desk that you use daily?
That’s the difference between RAM and flash (storage). When it comes to gaming, all the game files exist in flash storage on your phone (that’s your HDD or SSD or phone storage memory). When you start the game, those files are moved from storage and into memory as needed.
Let’s continue forward with the desk cabinet analogy. In the cabinet drawers you have your phone chargers, your power bricks, your notebooks, SD cards, batteries and a lot of other stuff you use on a daily basis.
A few friends are set to arrive at your place during the weekend for a gaming LAN party and they are going to bring over their computers, phones and tablets. You head on over to the basement to bring power extension cords that you rarely need to use. You have a lot of them so you put them in the drawer for easy access when needed.
At the end of the LAN party, on Sunday evening, everyone leaves so you take the power extension cords and put them in the basement again. This is exactly what happens with a game on your phone.
The drawers are RAM, the basement is the flash. When you fire up PUBG or Call of Duty Mobile the game’s 3D models, textures and sounds are taken from flash and copied/moved into RAM. They are kept there the entire time the application is running (even if in the background). When you quit the game (close it from multitasking / from the background) they are removed from RAM.
Hopefully this little analogy helps you understand the concept of RAM and flash better. Now, let’s see how more RAM affects your phone’s and game’s performance.
How does RAM affect mobile gaming performance?
Imagine your storage cabinet only has a small drawer. You can fit a lot of cables, SD cards, power cords and notebooks in there, but you can’t really keep it organized since everything is pilled up.
If you get a second drawer things can be sorted into “Computer accessories” (cables, power cords, SD cards) and “Note Taking accessories” (pens, notebooks, etc.).
You label the drawers as such. When you need a cable you look in the computer drawer. When you need a pen you like in the note drawer.
This helps you find the objects you need faster by just checking the label on the drawer.
It’s the same with RAM where objects are placed into memory and that memory location has an address that the game keeps track of. There’s an address for textures, models, sound and code.
The size of the RAM? It’s like the number of drawers. Think of 1 GB of RAM as 1024 drawers (or 1000 if you want to keep it simple). If your favorite PUBG weapon has a big texture that texture fits into 1 of the drawers and takes the entire space. If it’s a small, less detailed texture, then multiple textures of that type fit in the drawer.
The more drawers you have, the more stuff can be put in them. If you don’t have a lot of drawers then only SOME things that the game deems important are going to be put inside.
How does RAM affect FPS?
If you have less space (or drawers) than you need then you can end up with performance issues. Why? Because the game needs to carry the resources it needs from the basement into the drawers as it needs them. So the game takes textures and sound and music it doesn’t immediately need and takes them to the basement and picks up the things it needs and puts them in the drawer for easy access.
All that movement back and forth? That requires computing power and time to be performed and that slows down or interrupts the game, leading to an FPS drop or your game running slowly (by the way, if you want to learn more about FPS we wrote an article titled “Why Do Most Mobile Games Run At 30 FPS” in which we go into a lot of detail on the subject).
The more RAM you have the less back-and-forth a game has to do with moving stuff from one memory into another.
Does RAM increase the speed of the phone?
As mentioned in the previous chapter the more RAM, the more things can fit in memory and the less movement and carrying of data has to happen. However, remember that your phone doesn’t run a single program, it runs multiple apps.
The phone’s operating system (Android, iOS or Windows), the apps you have running (Facebook, Instagram, messenger), your web browser (and all of its tabs) + the game you want to play are all loaded into RAM when they are open and they all have to fit.
So, a phone with 4 GB of RAM might have enough to run a game that requires 2 GB but, in a lot of cases, that RAM might be taken up by other things running.
Here’s an example: let’s say you have an Android Phone and that phone has 4 GB of RAM. The operating system takes about 2 GB. You have WhatsApp or Telegram running in the background and they take 600 MB of RAM. You are left with 1.4 GB available.
Now you start a game that requires 1.95 GB of RAM. Your game will tell the phone “Hey buddy, I need more space for my stuff”. Depending on your operating system (and version) and the game’s code, the OS might close the background tabs of your browser and write all the messages from WhatsApp / Telegram to your phone’s storage, while the game will only load the most essential assets it needs (code + some graphics).
In total the phone will free up 300 MB of RAM and your game will try to just use 1.65 GB of RAM. As you play through your game more assets are swapped. The main menu graphics get removed from the game and the gun textures and sounds get loaded in.
Now let’s say you pause your game and go to check your messages. What happens? Game assets are unloaded from memory to free up space for your messaging app to load. This, once again, takes time and can make your phone feel slow and choppy.
It’s not that RAM increases the speed of your phone, instead it allows your phone to run as best as it can without hindering it with data retrieval calls from storage to memory.
Does RAM affect mobile graphics?
Every texture, sound or 3D model your phone uses takes space in RAM. The bigger the texture? The more space it needs in order to be accessed. Some games come with textures set to different sizes. When the game starts up it checks how much RAM is available and does something like this:
- Hey Phone, how much RAM do we have available?
- 2 GB OF RAM? Alright, I’ll load the low resolution textures for this game.
- 4 GB OF RAM? Great, I’ll load the medium resolution textures
- 8 GB OF RAM? Awesome, 4K mobile gaming it is! Bring up the next-gen graphics textures.
That’s one case in which RAM affects mobile graphics. Curious how different resolution textures look like and how the quality differs? Here’s an example of a horse with its textures at two different resolutions:
Does RAM affect battery life?
Yes, more RAM affects battery life in the sense that less intensive operations are required. Go back to our drawer and basement analogy from above and think of the battery as your energy. The more trips you have to do to the basement and back, the more energy you consume.
More RAM doesn’t increase your battery life but helps preserve it more.
Where To Next?
I write extensively about the mobile gaming industry, their tactics and how greed influences a game’s design. I believe that you might be interested in more articles on game monetization. So if you want to stick around, you can check out “How Do Free Mobile Games Make money“, “Why Do Mobile Games Have Fake Ads” and “Why Do Mobile Games Have In-App Purchases“.
There’s also a monster post (about 4000 words) that answers the question: “How Hard Is It To Make A Mobile Game“. It goes in depth with actual examples on how Experience, Resources and Financials affect the difficulty of developing and releasing new mobile games!
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