Free Ram Memory Mac
While reading thru some Apple forums, I found a question people asked a lot. While most responses were generally correct, I felt that all answers lacked some important details and as a result confused people even more. The purpose of this article to clarify those details as much as possible.
Additional Ways to Free up RAM on Windows or Mac. The best thing to do is to be proactive with your computer’s RAM so that you don’t have to worry about freeing up space. Use these additional ways to keep your RAM storage free. Install a Memory/RAM Cleaner. If you find that you do not have the time, or you just cannot manage to organize. Memory Clean is a menu bar item that shows how much memory you have. Feb 06, 2020 Clear RAM with Memory Cleaner. Use the special app to free up RAM on Mac – Memory Cleaner. Memory Cleaner is ABSOLUTELY FREE and allows you to automatically clean up inactive memory and speed up your Mac. Follow these steps to clear RAM with Memory Cleaner: Launch Memory Cleaner. The app will constantly be active from the toolbar on your.
First, let’s answer the first question from the title of the post.
What is wired memory?
Wired memory on Mac is reserved for the macOS kernel and its data structures, and it cannot be paged out. The normal size of the wired memory is around 2GB. User applications add on average 1MB per instance, and too many running programs can contribute to high wired memory usage.
Now, let’s dive into more technical details.
When the Mac suddenly becomes too slow, the laptop owners start browsing forums and learn to check the memory tab in Activity Monitor.
The screenshot above which I made after rebooting the Mac indicates that my Mac has 8GB of Physical Memory and 2.33GB of it is in the Used Memory bucket. The used memory then consists of App Memory (1.2GB) and Wired Memory (1.13GB).
Why do people ask about Wired memory?
Wired memory is a memory that can’t be compressed or paged out to your startup drives, so it must stay in RAM. Moreover, other processes can’t borrow it.
The key phrase here is “can’t be paged out.”
Before we proceed further let me explain what paging is.
The architecture of modern computers was designed in the 20th century. Any computer has three main parts: processor, RAM (random access memory) and storage (disk, tape, punched cards, etc.).
The processor works directly with RAM because the latter is thousands of times faster than HHD or SSD. Besides the speed, there are two more differences between RAM and HHD:
- RAM needs constant power. When a computer shuts down or restarts, the data in RAM gets wiped. Hard drives preserve data even when the computer is off.
- RAM is much more expensive. For instance, for an additional $200, you can buy either 8GB more RAM or 128GB more SSD when purchasing a new MacBook Pro.
The last point is significant. If RAM was cheap, then Apple would stuff its laptops with tons of memory, and nobody would care to read this article. But since its more expensive than disk storage computer engineers invented memory swapping or paging.
Let me use a whiteboard analogy.
Imagine, you work in a startup company which rents couple desks in a coworking space. Amenities in a coworking environment include unlimited coffee and beer, Wi-Fi, bike storage, and a whiteboard.
When Team A needs to brainstorm the Next Big Thing, they go to the whiteboard and start writing down some ideas. Unfortunately, there is only one whiteboard on the floor. Team B wants to brainstorm their TNBT too, and they also need some whiteboard space.
Team A graciously agrees to share some of the whiteboard space. Then another team comes, and another. With each team, the amount of free space shrinks.
When the available area gets too tight, teams decide to write down some of their ideas on the paper and clear the piece of the whiteboard for new ideas. When they need to access their old ideas, they search thru past papers and copy them to the whiteboard.
Memory management in modern operating systems works similarly. In this case, a whiteboard is a physical memory which is shared by apps (teams). When apps request additional memory, and there is no more free space, the OS checks all memory pages.
The OS tries to find ones that were not used recently and copies them to the disk. Apps do not write down unused memory like in whiteboard example, the OS does. When the app needs back that data, the OS reads it back to RAM from the disk.
In theory, more disk storage the computer has more RAM can be extended by paging. The reverse is also true, in case of little or no free disk space swapping is almost impossible.
This wonderful mechanism, however, has a significant flow: disk is thousands of times slower than RAM. When there is no enough memory, the system keeps paging in and out data continuously, which causes so-called disk thrashing.
In the latter case, the computer, instead of executing programs keeps moving data making the life of a computer user miserable.
So what it has to do with wired memory? Continuing the analogy, imaging the coworking administration decided to block the quarter of the whiteboard and write a schedule of events on it. Plus they disallowed any team to wipe off the schedule.
More space the administration takes less whiteboard space teams can use. More wired memory the macOS uses fewer memory apps can share.
By the way, if you were wondering what represents Cached Files in the first screenshot, it’s a memory that was used by an app which was recently terminated. It’s as if Team A decided to go to a nearby restaurant to grab some lunch.
If by the time they come back, their ideas are still on the whiteboard, they can start from where they left. If not, then they have to copy everything from their papers back to the whiteboard.
Cached Files is a mechanism which macOS uses to speed up the recently closed applications in case if a user wants to start them again. If meantime another app needs more memory, the OS will claim it from Cashed Files.
So, if you see too much Cached Files don’t worry, it’s same as free memory.
If you need proof, try following in Terminal:
- In the Terminal app type sudo purge and hit Enter
- Type in the admin password
When I ran this command, the only thing that has changed in Activity Monitor was Cached Files: its size dropped from 1.89GB to 594MB.
Is it ok to use sudo purge? There is no harm because all it does is clear unused memory. But it also doesn’t do anything valuable. macOS can release unused memory when apps ask for more.
What’s included in the Wired memory?
According to Apple documentation, wired memory is a part of memory reserved for OS kernel and its data structures. Following kernel objects belong to the wired memory: Virtual Memory objects, virtual memory and I/O buffer caches, various drivers.
User applications do not directly work with the hardware; they send requests to kernel drivers and those, in turn, perform hardware operations. For instance, the internet browser does not send pixels to the MacBook screen. Instead, it sends requests to the video driver, which then changes colors of pixels on the screen.
However, user apps can also influence how much of wired memory is used, although indirectly.
Following is a table with some (not all) types of objects user apps indirectly create in the wired memory. Note that the data in the table is outdated, but it at least gives some idea why the wired memory changes every time we load or unload an app.
Let me explain some of the objects in the table on the example of the Google Chrome browser. When I first started Chrome, it created several processes: one Google Chrome and 8 Google Chrome Helpers. The wired memory immediately jumped to 1.35GB.
Each line in the Activity Monitor is a process: an application instance. Each process is a collection of threads and threads perform actual work on the computer. If data in Table 1 was current, we could count that Google Chrome process added 16KB to store process data, plus 46 * 21KB = 966KB for threads.
Chrome is an interesting app. Every time you open a new tab, it starts additional helpers. Each helper is a separate process, and each process spawns numerous threads.
When I opened one tab, the number of Chrome helpers jumped from 8 to 16. After opening a second tab the number of helpers increased to 24, and after third to 26. After opening three tabs, the wired memory size increased to 1.61GB.
As you can see each process indirectly increases wired memory because macOS has to record those threads somewhere.
And this is not all. While Apple claims that wired memory is reserved for kernel and some objects which describe user processes, some applications can tap into the wired memory directly.
For instance, if you ever used virtualization software such as Parallels Desktop or VMWare, you should know that they use the wired memory directly to improve the performance.
If you think about this, it makes perfect sense. Virtual frameworks are designed to act like real machines so that OS running inside can handle the memory the way they always do. For instance, if you run macOS virtual machine on Mac, the macOS will create its version of wired memory inside VM.
After digging a bit in the Kernel Programming Guide, I found that applications can allocate memory in the kernel by calling kmem_alloc_wired function instead of regular alloc.
Now, what all of this means in practice?
How to free up memory on Mac
There are two main reasons for the high usage of wired memory:
1) Some applications modify the kernel and use wired memory deliberately. Examples are drivers and applications working on the kernel level such as antiviruses, or virtual machines. If for instance, there are some widgets in the Mission control, turn off those you don’t need.
In the case of virtual machines, the remedy is to limit the memory configuration. For example, if the Windows VM is configured to use 8GB of RAM lower it to 4GB.
2) When too many applications are active, they still use RAM. Unlike Windows, where clicking on close button unloads the app, in macOS, the app continues staying in memory. You can tell them by a little dot under the icon in the Dock.
Use Command and Q key combination to quit the app altogether. If some apps still stay in the memory rebooting the computer sometimes can fix the problem.
And finally, high wired memory usage is not always a sign of a problem. In the following example used memory was almost 31GB on a 32GB Mac, and wired memory accounted for the bulk of used (26.61GB).
However, look at the left side of the screenshot: Memory Pressure. Memory Pressure section in Activity Monitor can have one of 3 colors like a traffic light: green, yellow, and red. If memory pressure color is red, then more RAM is needed. In case if it’s green, then there is enough memory for the current load.
Wired memory does not get released immediately when an application quits. It gets cleared by a garbage collection process which may take some time, and during this time the wired memory size may be too high.
Resources:
Image credit: Flikr
macOS does a pretty good job of managing system memory and, as long as you have a reasonable amount of space free on your boot drive, it can also swap data between RAM and disk when it needs to. However, even the most recent Macs only ship with 8GB of RAM as standard, which can be tight for apps hungry for memory.
In addition, some apps misbehave and “leak” memory, meaning they hog more than their fair share leaving less for other apps. The solution is to use a memory cleaning app to free up RAM. Here, we selected the top 10 best Mac memory cleaners that will help you control memory usage.
If you want to know just how much RAM each app you’re running is consuming, go to Applications > Utilities and launch Activity Monitor. That will display all running processes, including browser tabs, and show you how much RAM they are using.
CleanMyMac X
CleanMyMac X has two methods for cleaning memory. The first is its Maintenance module that has a Free Up RAM tool that can grab gigabytes of memory back with a couple of clicks. The other tool is the CleanMyMac X menu bar item. When it’s running, it will pop up a warning whenever your Mac runs low on RAM and offers to free some up for you.CleanMyMac X also has a System Junk tool that clears out junk files from your boot drive, giving you more space for virtual RAM. The app is notarized by Apple, which means it’s safe to use on a Mac. Download the free version to try out all features.
2. Memory Clean
Memory Clean is a menu bar item that shows how much memory you have available and what is occupying the rest. It also displays the apps that are eating out your Mac’s resources and inactive apps occupying RAM. There are two options for cleaning, Clean and Extreme Clean, and you can also set Memory Clean to free up RAM automatically, so you never have to think about it.
3. Nektony Memory Cleaner
Memory Cleaner is also a menu bar app with a clear, easy-to-read dashboard-style layout. When you click on it, Memory Cleaner displays how much RAM you have in use as a percentage of the total, as well as the apps that are using the most memory. You can then free up RAM with one click.
Memory Cleaner also shows you how much space is being used by junk files on your Mac and allows you to free some of that space up, too.
4. Memory Diag
Memory Diag is a RAM cleaning tool that not only looks good but does a great job of letting you know when memory is running low. Like others on this list, it’s a menu bar item. In this case, it displays what it calls a memory pressure graph that’s color-coded so you can easily see how much memory your Mac has free. If it’s in the green, no problem. If the meter is deep in the red, though, it’s time to press the recycle button to free up memory. Memory Diag also shows you which apps are taking up most RAM.
5. Memory Magic
Memory Magic is so-called because it works away in the background performing tasks to optimize memory and free up space for applications that need it. If you click on its menu bar item, you’ll see how much RAM you have still available and can, if required, manually force it to recover memory. History graphs allow you to see how often you come close to running out of memory space.
6. Instastats
This menu bar app displays how much memory is occupied and color codes wired, active, inactive, used, and free, so you can see precisely how RAM is allocated at any given time. It does a similar job for CPU, disk space, network, and battery. And it has a Notification Center widget that provides the same information. It automatically cleans memory every five minutes if it is running low.
7. Memory Purge for Mac
Memory Purge is another menu bar tool that helps quickly clean memory. It looks clear and simple and does what you expect: it presents brief memory usage stats and specifies which apps are using a significant amount of memory. You can then click then free up RAM with a single click.
Free Ram Memory On Mac
8. Memory Check
Memory Check can display a memory meter in your menu bar showing the percentage of memory currently in use. It will also warn you when memory usage goes beyond a certain level and allow you to free up space. There’s a Notification Center widget and support for Dark Mode.
Free Ram Memory Mac Air
9. SystemPal
SystemPal combines a memory monitor and cleaning tool with other features like a mini music player and screenshot utility, as well as CPU and network monitors. The memory monitor displays a pie chart showing how memory is allocated and lists the most memory-hungry processes currently running. There’s also a button to free up memory.
Memory For A Macbook
10. iCleanMemory
Macbook Ram Memory
iCleanMemory is the simplest of all the tools here. The menu bar item shows how much memory is in use and how much is free. Click on its icon, and it displays how memory is currently available. If it looks low, press the optimize memory button, and it will free some up.
Mac Ram Finder
There are lots of options for memory cleaners on the Mac. Some just do one job and sit in the menu bar. Others combine multiple features and allow you to customize them. Which one you choose depends on whether you just want a tool to clean up memory or whether you want other features to help keep your Mac running smoothly.