Performance

Activity Monitor is the free system monitor built into macOS. How to open it, and how to read the five tabs, including the numbers that look scary and aren't.

Press Option-Command-Esc. That's the Mac's Ctrl+Alt+Delete, and it opens the Force Quit window. Here's every way to close a frozen app, in ascending order of force, and what to do when force quitting itself stops working.

macOS keeps battery health and cycle count on two different screens, and tells you neither what your model was rated for nor when the wear actually matters. Here is where both numbers live, what they mean, and how to decide between a new battery and a new Mac.

Unified memory changes how a Mac's memory is wired, not how much a gigabyte holds. Here's what Apple changed on Apple silicon, where the claim that 8 GB behaves like 16 GB came from, and how to decide how much to buy on a Mac you can't upgrade later.

"Google Chrome Helper" is Chrome's own process for displaying web pages, and seeing thirty of them in Activity Monitor is normal rather than an infection. Here's what each version of the name means, how to find the tab responsible, and which popular advice about it stopped working years ago.

Looking for an iStat Menus alternative? For pure sensor readouts, iStat Menus ($11.99) and Stats (free) are hard to beat. If you want live vitals plus the fix next to each one, here's the honest difference.

macOS has no built-in CPU temperature readout. Here's how to check it on Apple silicon with powermetrics, what's a normal range, and why the process running hot matters more than the number.

Find out what's using your Mac's network: Activity Monitor's Network tab for per-app data, nettop and lsof for live connections and hosts, and how to see which app is quietly phoning home.

The best Mac menu-bar system monitor depends on what you want: pure sensor detail (iStat Menus, Stats), a monitor-plus-cleaner suite (Sensei), or live vitals with the fix beside each one (Plumby). Honest picks, with prices.

A slow Mac is almost always one of four things: memory pressure, a runaway process, too many login items, or background work after an update. Here's how to tell which, and fix the real cause.

accountsd using high CPU on your Mac is the Accounts daemon stuck in a broken sync loop, almost always one iCloud or mail account. Here's how to find the offending account and fix it.

backupd using high CPU on your Mac is Time Machine running a backup, usually normal and self-throttling. Here's when it's expected, when it isn't, and how to bring it back under control.

bluetoothd using high CPU on your Mac isn't normal. It's almost always a specific flaky Bluetooth device or an OS bug. Here's how to isolate the device and the fixes that actually work.

cfprefsd using high CPU on your Mac is the preferences daemon, and it's almost always a badly behaved app or a corrupt preference file. Here's how to find the culprit and reset it safely.

coreaudiod using high CPU on your Mac is Core Audio, and it's usually a symptom of another app monitoring the mic or a buggy audio driver. Here's how to find the real cause and reset it safely.

lsd using high CPU on your Mac is the Launch Services database daemon: the registry of which app opens which file. Here's why it spikes, how to rebuild the database, and why it's not launchservicesd.

mdworker and mdworker_shared using high CPU on your Mac are Spotlight's indexing workers reading your files. Here's why they spike, why several at once is normal, and the safe fixes.

mediaanalysisd using high CPU on your Mac is the on-device engine behind Live Text and Visual Look Up, not face recognition. Here's why it spikes, why it's private, and how to calm it down.

sharingd using high CPU on your Mac powers AirDrop, Handoff, and Continuity, and usually spikes on a stuck AirDrop or constant wireless retries. Here's how to calm it, and the privacy angle worth knowing.

softwareupdated using high CPU on your Mac is the Software Update daemon checking, downloading, or installing updates. Here's why it sometimes gets stuck, and how to fix it safely.

syspolicyd using high CPU on your Mac is Gatekeeper checking apps as they launch. Here's why it spikes (often an app launching binaries in a loop) and the safe way to calm it.

trustd using high CPU on your Mac is the certificate-trust daemon checking whether certificates are still valid. Here's why it spikes or hangs, and how to fix the persistent 100% case.

Is 8 GB RAM enough on a Mac? On Apple silicon, unified memory and fast SSD swap make it fine for light-to-moderate use; here's when to buy 16 GB+.

Mac slow after a macOS update? It's usually temporary background work (Spotlight reindexing, Photos re-analyzing, iCloud re-syncing), not a broken Mac.

A slow Mac startup usually means too many login items and leftover launch agents loading at boot. Here's how to trim them safely, starting in System Settings.

bird, cloudd and nsurlsessiond using high CPU on your Mac? They're iCloud's sync daemons, not a virus. Why they spike, what's normal, and how to fix a stuck sync.

photoanalysisd high CPU on your Mac isn't a virus; it's Photos scanning your library for faces, scenes, and Memories. Here's why it spikes and what to do.

Mac memory pressure, not free RAM, is the real signal. Here's what green, yellow, and red mean in Activity Monitor, and why RAM cleaner apps don't help.

MacBook fans loud and running hot? Fans spinning up under load is normal; the fix is finding which process is working the CPU or GPU. Here's how to check.

Wondering what's draining your Mac battery? Find it with the battery menu's Significant Energy list, Activity Monitor's Energy tab, and pmset; no app needed.

Chrome using too much memory on Mac is mostly its multi-process design: each tab and extension is a separate process. Here's how to find and fix the real hog.

WindowServer high CPU on a Mac isn't a virus; it's the process that draws every window and pixel. Here's why it spikes and how to bring the load down safely.

High kernel_task CPU on Mac usually isn't a virus; it's macOS managing heat by holding back the CPU. Here's why it spikes, what's normal, and the safe fixes.

mds_stores using high CPU on your Mac usually isn't a virus; it's Spotlight rebuilding its index. Here's why it spikes, what's normal, and the safe fixes.