MacBook – Why is iBooks.app taking 650 MB memory on macOS 10.14.5

To answer your question about performance, it really depends on what you're wanting to do.

CPU: To put it simply, CPU speed defines how quickly your computer can process data. As you're asking the question in a Mac forum I'll assume you want to by a mac. The most basic MacBook Air laptop has 1.7GHZ dual core processor, which means it has two 1.7GHZ processors. For basic computing this is more than enough, but if you wanted to do something a bit more labour intensive, say photo editing or graphic design or high end gaming, it'd probably be a bit slow. If you look at the slightly more advanced machines apple has on offer like the macbook pros or the iMacs then the processors are more in the 2.5GHZ - 2.9GHZ range, this is plenty for most high end applications. Finally the top of the range machines are the Mac Pros. They have quad core, 8 core and 12 core options upward of 3.2GHZ. These are great machines if you have the money and will make photoshop run a little faster, but not really a necessity unless you want to do some really high end stuff like Animation or complex video editing.

Memory: Memory consists of what can be considered your long term memory (your hard drive) which is sometimes called "storage" and your short term memory or RAM (stands for Random Access Memory if you're geeky enough to be interested) which is what the term "memory" is normally referring to. Ram controls how much your computer can store in the short term to process. Most basic PC's and the most basic macbook airs come with 2 gigs of ram nowadays which is more than enough for basic applications. However, again if you're looking to do photo editing or graphic design or online gaming then you really should be looking at between 4g and 8g otherwise your computer won't have enough memory to process lots of different functions at the same time. And of course, if you're a budding Peter Jackson about to make the next lord of the rings film and you need to be able to render an army of mediaeval monstors, then the mac pro ranges from 16g to 64g of ram.

Hope this answers your question better.

The kernel_task process in question is likely your process running.

You can try freeing up "inactive memory" with the purge command in Terminal, just type purge and hit return when the inactive memory gets to be a good percentage of the used memory.

You can also try running your process without the gui, or without the window server running. This will free up memory and processor resources.

• Set your login window to require name and password from the accounts control panel in system preferences, turn off auto login if enabled.

• Then reboot to free up memory.

• from the login window (if set as username/password) type >console in the name field, hit enter, and when the window server quits...

• log in at the console, shortname & enter password when prompted

• type screen and hit return

screen man page - so you can have another term to watch with top; will use less resources than running gui. control-a then c to create new terminal, control-a then n to move between the two scrreens

run your process in one, run top -u -s5 to run a utility like activity monitor so you can monitor your process

when done, just exit out of both screens, and then exit out of the console to launch the window server and return the login window and back to gui