Over time, your Mac can start performing slower than usual due to the accumulated cruft clogging up the system, including temporary files, various caches, streaming data and so forth.
Aside from low disk space, the RAM (or lack of it) is the second major cause of slowdowns.
When you open an app, its binary gets loaded from storage into the RAM so that the CPU can fetch and execute code. Like all multitasking operating systems, macOS dynamically manages the RAM on your behalf so that you’re able to run more apps at the same time than fit into it.
macOS’s memory management works pretty well—most of the time, the Activity Monitor app shows the RAM as being nearly 100 percent utilized. This is by design—as a rule of thumb, the RAM wants to be packed to the gills all the time because loading content from storage is slower than fetching from the RAM.
But sometimes macOS’s memory management may fail to purge loaded content from the RAM, straining resources. macOS also periodically flushes the system caches, but sometimes caches may not be properly emptied.
Either way, this will cause your machine to start stuttering and exhibiting signs of reduced performance such as longer app load times and slower multitasking. Follow along with iDB as we teach you how to manually force macOS to clear out the RAM and flush the disk caches.
How to speed up your Mac
You can resolve the slowdowns with or without rebooting.
Macs are designed to go weeks and months without restarting but I still shut down my computer at the end of the day and restart it in the morning as doing so prompts macOS to empty out everything in the RAM and clear all the disk caches.
If you’re not comfortable working with the command line in Terminal, you should restart your Mac once per day and you’ll be good.
In some cases, a reboot may fail to clear the RAM and disk caches, but that’s what Terminal is for. Thanks to the command line in macOS, you can force macOS’s RAM and cache-cleaning processes to spring into action.
1) Open Terminal from your Applications/Utilities folder.
2) Execute the purge command with administrative privileges by typing the following command into the Terminal window, then hit Enter to run it:
You may be asked to enter the password for your Mac account.
Clearing out the RAM and disk cache contents should take no longer than a few seconds unless your Mac is running really low on memory and storage space. You’ll see no confirmation message when the operation has been completed.
The command line method is especially convenient if you don’t want to interrupt important work by restarting the machine. Just load up the Terminal app and execute the aforementioned commands to give your Mac a boost without restarting.
Time to upgrade RAM/SSD?
Of course, the purge command is not the magical remedy for all your Mac slowdown woes. In fact, your Mac have insufficient RAM for what you’re typically using it for.
If you’re someone who edits photos/videos in pro apps, you’ll need as much RAM as you can get. Four gigabytes is the bare minimum these days for light usage and 8GB RAM is recommended for everyday multitasking like surfing the web, checking email, using social media, consuming content and editing media.
Aside from the RAM, you may outfit your Mac with a faster SSD which’ll immediately give you a noticeable boost in performance—especially if you’re coming from an HDD-based Mac.
Need help? Ask iDB!
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