There is a whole jungle of apps out there that show you the status of your computer in the menu bar, on your desktop or in the Dock, but did you know that the best tool of them all comes with macOS?
Activity Monitor is an application that allows you to monitor exactly what is going on with your computer at all times by showing you how much memory, cpu, network and disk space is currently being used. It can also show you which application is using the resources and it allows you to quickly kill a process that is going haywire or has stopped responding.
The handiest feature of all is that it can show the status in the Dock so that you can quickly see if something has gone wrong and prevent crashes. Open up Activity Monitor (in Utilities inside Applications), then select the type of information you want from the View, Dock Icon menu. To make the most of this we’d recommend setting Activity Monitor to automatically launch when you log in. This is done by right clicking the icon in the Dock and choosing Options, Open at Login.
Keeping Activity Monitor in the Dock also has all sorts of unexpected benefits, for example it is very handy if you feel that your computer is getting slow. Most Macs that are kept in good shape can live for many years and still be as fast as the day they were purchased. The key to this? Keep an eye on the memory usage.
If all the memory is being used up soon after booting up your computer macOS will start using the hard drive to give you more memory than what is physically available (this is called swapping). The catch is, swap memory is much much slower than real RAM memory so you will notice this by feeling that the computer gets much slower. The solution? Use Cocktail to purge inactive memory (System > Memory), try cleaning up the applications that run in the background or install more memory.
Activity Monitor can also help you debug other problems. Battery life is directly dependent on how much load there is on the processor so if the battery in your laptop doesn’t last as long as you expect, have a look at how the processor is being used. Generally, to get anywhere near Apple’s specified battery life you should be around 10-20% usage so if the processor is averaging more than that some process is draining your battery.
To reset a login password in OS X Mountain Lion or later, restart the Mac and hold down Command-R to boot into the Recovery HD partition. From the Utilities menu, choose Terminal to open it. In Terminal type:
and press Return.
In macOS Sierra and macOS High Sierra, an Reset Password assistant will launch. Choose the user account or admin account you want to reset the password for. Enter a new password, confirm the new password, set (if you like) a password hint and then click on "Next" to set the new password for the account in question. Choose to "Restart" the Mac and when the Mac boots up, use the newly reset password to login to the computer.
In OS X Mountain Lion, OS X Mavericks, OS X Yosemite and OS X El Capitan, a Reset Password window will appear that will list all the bootable volumes attached to your Mac. Select the volume that contains the account you want to reset and choose the user name that needs its password reset. Enter and verify a new passwords in the appropriate fields and, if you like, enter a password hint. Click Save and the new password is applied to the account.
Time Machine is the simplest way to keep regular backups of a Mac. On some rare occasions though, Time Machine may get stuck on the "Preparing backup…" stage for an inordinately long amount of time, causing a backup to never start. So lets fix this specific Time Machine issue.
The first thing you need to do is cease the currently failed backup attempt:
• Open System Preferences from the Apple menu and click "Time Machine"
• Click the (x) icon on the right side of the progress bar to stop the backup attempt
When the progress bar disappears and it no longer says "Preparing backup…" you're good to begin the troubleshooting process.
• Open the Time Machine drive in the Finder and navigate to the "Backups.backupd" folder
• Open the folder within Backups.backupd that is the name of the current Mac which is stuck on preparing
• Put this directory into "List View" and sort by ‘Date Modified', or just search the folder for a file with a ".inProgress" file extension
• Delete the "xxxx-xx-xx-xxxxxx.inProgress" file. The .inProgress file is always in the form of xxxx-xx-xx-xxxxxx.inProgress, where the first 8 digits are the year-month-day (date) and the next 6 or so digits are random numbers, followed by the inProgress file extension.
• Restart your Mac
• Once rebooted, let Spotlight run completely (you can either just wait it out or watch the mdworker, mrs, and related processes in Activity Monitor). This should cause macOS to re-index the attached Time Machine drive if it's needed, which may be getting in the way of Time Machine backing up properly thus causing the computer to get stuck on "Preparing backup..." for a very long time.
• Start a back up yourself. Pull down the Time Machine icon and choose "Back Up Now". You will still see a "Preparing backup…" message but it should be gone within a few minutes, depending on the size of the hard drive, the speed of the Mac, and the size of the backup to be made. At this point, your Time Machine backup will proceed as expected, so just let it run and you're good to go again.
If you have a MacBook, MacBook Air or MacBook Pro, you can check the battery cycle count to get an idea of overall battery health. Here’s how you can do that yourself, right from the macOS built in system management functions.
This works for all batteries in portable Mac models.
• Pull down the () Apple menu and choose "About This Mac".
• Click the "System Report…" button.
• Under Hardware, select "Power" and look for "Cycle Count" under the "Battery Information" portion.
The number shown is the cycle count of the current battery. A battery charge cycle is when the battery has been drained to 0% and then refilled to 100% of it's maximum capacity. Knowing the cycle count is helpful if you suspect your battery is having problems retaining a charge. Apple says new notebook batteries are designed to retain 80% of original capacity after 1000 cycles. If your battery is performing at less than expected and is still under warranty, it may be a good idea to schedule an appointment with an Apple Genius.
Those who use external Bluetooth devices with a Mac, whether it's a keyboard, mouse, headset, or anything else, are probably aware that connection strength between the device and the computer is going to directly impact how usable the device is.
If your Bluetooth device connections seem flakey, or if your wireless keyboard or mouse isn't as responsive as you think it should be with your Mac, there is a easy way to check Bluetooth signal strength in macOS. Simply Option (Alt) click the Bluetooth menu bar item, then move the mouse cursor over the Bluetooth item you want to check the signal strength for and look for "RSSI".
RSSI (Received Signal Strength Indicator) can be a bit weird to read, but essentially a higher number means a better connection, and a lower number means a worse connection. Note however that the numbers are negative, so that may read opposite to what you'd expect. For example, a connection of -45 is significantly stronger and better than a connection of -100, which is weaker and more likely to have issues. The rough guidelines below may help read the connection, though the precise signal you get is going to vary on other factors we’ll discuss below:
-40 to -55 is a very strong connection
-70 and above represents a good connection
-100 and below represents a bad connection
-110 and below is almost unusable
The two most likely reasons for a bad Bluetooth connection are low batteries and heavy interference from something in the environment. Batteries are easy to test, all you need to do is swap in a new set of batteries or charge the device in question and see if the RSSI increases and if the device becomes more stable. Environmental factors can be trickier to track down, but if you see a huge drop in the RSSI when you move a headset behind a fireplace for example, you can surmise that something in the wall is causing the interference and you should rearrange the equipment accordingly. It's also vaguely possible that the device itself has a defective antenna, though that’s fairly rare for most quality devices.