Find what is slowing your Mac

Steps

1. 01Step 1 of 7

   Step 1. Read the sentence on Overview

   Press ⌘1 for Overview. The stage tells you in words whether anything needs attention, and names the busiest app under it. For example: "Lumen Edit uses 212.4% CPU across 6 processes, where 100% is one core."

   OverviewUnderstand what your Mac is doing, and what is using its resources.

   SummaryDashboardSearch or jump to…⌘KPauseRecord

   Live10:42:18

   No warning in assessed readings.

   Lumen Edit uses 212.4% CPU across 6 processes, where 100% is one core.

   Pressure NormalThermal Nominal

   486 processes · 3,912 threadsUp 4d 3h · swap 0 bytes

   Export Visual Snapshot…

   Apple M4 Prosystem on chip · 14 CPU cores · 48 GB unified memory

   CPUwhole Mac · every 2s

   24%

   User17.6%System6.4%Idle76.0%

   GPUevery 5s

   18%

   Renderer16%

   Tiler9%

   Neural Engine

   0.42W

   power, not utilizationpeak 2.31 W · 120 s

   Unified memoryshared by CPU, GPU and Neural Engine

   21.4GBestimated used of 48 GB · 44.6%

   App14.2 GBWired4.1 GBCompressed3.1 GB

   Cache12.8 GBFree13.8 GB

   Component power

   14.2Wpeak 31.6 W

   CPU 9.6 · GPU 4.2 · ANE 0.42 W

   Diskevery 2s

   Read2.1 MB/s

   Write1.1 MB/s

   Networkevery 2s

   Received1.6 MB/s

   Sent210 KB/s

   Live timelineLatest 120 seconds on one clock · hover to rewind the stage, click to pin · gaps stay visible

   CPUevery 2s

   24%User 17.6% · System 6.4%

   100%0

   GPUevery 5s

   18%Renderer 16% · Tiler 9%

   100%0

   Neural Engineevery 5s

   0.42 Wpower, not utilization

   2.5 W0

   Memoryevery 2s

   21.4 GBPressure Normal

   48 GB0

   Diskevery 2s

   3.2 MB/sRead 2.1 · Write 1.1 MB/s

   ↑ 20 MB/s↓ 20 MB/s

   Networkevery 2s

   1.8 MB/sReceived 1.6 MB/s · Sent 210 KB/s

   ↑ 5 MB/s↓ 5 MB/s

   Apps using CPUApp helpers are included · 100% means one busy core

   L

   Lumen Edit6 processes

   212.4%

   K

   Kite Browser23 processes

   38.6%

   F

   Forge IDE14 processes

   24.9%

   H

   Harbor9 processes

   18.2%

   R

   Roundtable5 processes

   9.8%

   Sample 10:42:18Explore all processes

   What the numbers meanObservations from the displayed sample

   Info

   Lumen Edit leads measured CPU usageIt uses 212.4% CPU across 6 processes, where 100% is one core.

   Info

   Memory pressure is normalmacOS is meeting demand without heavy compression or swap.

2. 02Step 2 of 7

   Step 2. Check the two chips before blaming the processor

   Under the sentence are two chips. Pressure is how hard macOS is working to find memory. Thermal is how hot the Mac says it is.

   If Pressure reads Elevated or Critical, the slowness is about memory, and Read memory the right way is the guide you want. If Thermal reads Serious or Critical, the Mac is slowing itself down to cool off.

   OverviewUnderstand what your Mac is doing, and what is using its resources.

   SummaryDashboardSearch or jump to…⌘KPauseRecord

   Live10:42:18

   No warning in assessed readings.

   Lumen Edit uses 212.4% CPU across 6 processes, where 100% is one core.

   Pressure NormalThermal Nominal

   486 processes · 3,912 threadsUp 4d 3h · swap 0 bytes

   Export Visual Snapshot…

   Apple M4 Prosystem on chip · 14 CPU cores · 48 GB unified memory

   CPUwhole Mac · every 2s

   24%

   User17.6%System6.4%Idle76.0%

   GPUevery 5s

   18%

   Renderer16%

   Tiler9%

   Neural Engine

   0.42W

   power, not utilizationpeak 2.31 W · 120 s

   Unified memoryshared by CPU, GPU and Neural Engine

   21.4GBestimated used of 48 GB · 44.6%

   App14.2 GBWired4.1 GBCompressed3.1 GB

   Cache12.8 GBFree13.8 GB

   Component power

   14.2Wpeak 31.6 W

   CPU 9.6 · GPU 4.2 · ANE 0.42 W

   Diskevery 2s

   Read2.1 MB/s

   Write1.1 MB/s

   Networkevery 2s

   Received1.6 MB/s

   Sent210 KB/s

   Live timelineLatest 120 seconds on one clock · hover to rewind the stage, click to pin · gaps stay visible

   CPUevery 2s

   24%User 17.6% · System 6.4%

   100%0

   GPUevery 5s

   18%Renderer 16% · Tiler 9%

   100%0

   Neural Engineevery 5s

   0.42 Wpower, not utilization

   2.5 W0

   Memoryevery 2s

   21.4 GBPressure Normal

   48 GB0

   Diskevery 2s

   3.2 MB/sRead 2.1 · Write 1.1 MB/s

   ↑ 20 MB/s↓ 20 MB/s

   Networkevery 2s

   1.8 MB/sReceived 1.6 MB/s · Sent 210 KB/s

   ↑ 5 MB/s↓ 5 MB/s

   Apps using CPUApp helpers are included · 100% means one busy core

   L

   Lumen Edit6 processes

   212.4%

   K

   Kite Browser23 processes

   38.6%

   F

   Forge IDE14 processes

   24.9%

   H

   Harbor9 processes

   18.2%

   R

   Roundtable5 processes

   9.8%

   Sample 10:42:18Explore all processes

   What the numbers meanObservations from the displayed sample

   Info

   Lumen Edit leads measured CPU usageIt uses 212.4% CPU across 6 processes, where 100% is one core.

   Info

   Memory pressure is normalmacOS is meeting demand without heavy compression or swap.

3. 03Step 3 of 7

   Step 3. Open the busiest app

   On the right, Apps using CPU lists the five busiest apps with their helpers counted in. Click the top row. Processes opens with that app selected.

   OverviewUnderstand what your Mac is doing, and what is using its resources.

   SummaryDashboardSearch or jump to…⌘KPauseRecord

   Live10:42:18

   No warning in assessed readings.

   Lumen Edit uses 212.4% CPU across 6 processes, where 100% is one core.

   Pressure NormalThermal Nominal

   486 processes · 3,912 threadsUp 4d 3h · swap 0 bytes

   Export Visual Snapshot…

   Apple M4 Prosystem on chip · 14 CPU cores · 48 GB unified memory

   CPUwhole Mac · every 2s

   24%

   User17.6%System6.4%Idle76.0%

   GPUevery 5s

   18%

   Renderer16%

   Tiler9%

   Neural Engine

   0.42W

   power, not utilizationpeak 2.31 W · 120 s

   Unified memoryshared by CPU, GPU and Neural Engine

   21.4GBestimated used of 48 GB · 44.6%

   App14.2 GBWired4.1 GBCompressed3.1 GB

   Cache12.8 GBFree13.8 GB

   Component power

   14.2Wpeak 31.6 W

   CPU 9.6 · GPU 4.2 · ANE 0.42 W

   Diskevery 2s

   Read2.1 MB/s

   Write1.1 MB/s

   Networkevery 2s

   Received1.6 MB/s

   Sent210 KB/s

   Live timelineLatest 120 seconds on one clock · hover to rewind the stage, click to pin · gaps stay visible

   CPUevery 2s

   24%User 17.6% · System 6.4%

   100%0

   GPUevery 5s

   18%Renderer 16% · Tiler 9%

   100%0

   Neural Engineevery 5s

   0.42 Wpower, not utilization

   2.5 W0

   Memoryevery 2s

   21.4 GBPressure Normal

   48 GB0

   Diskevery 2s

   3.2 MB/sRead 2.1 · Write 1.1 MB/s

   ↑ 20 MB/s↓ 20 MB/s

   Networkevery 2s

   1.8 MB/sReceived 1.6 MB/s · Sent 210 KB/s

   ↑ 5 MB/s↓ 5 MB/s

   Apps using CPUApp helpers are included · 100% means one busy core

   L

   Lumen Edit6 processes

   212.4%

   K

   Kite Browser23 processes

   38.6%

   F

   Forge IDE14 processes

   24.9%

   H

   Harbor9 processes

   18.2%

   R

   Roundtable5 processes

   9.8%

   Sample 10:42:18Explore all processes

   What the numbers meanObservations from the displayed sample

   Info

   Lumen Edit leads measured CPU usageIt uses 212.4% CPU across 6 processes, where 100% is one core.

   Info

   Memory pressure is normalmacOS is meeting demand without heavy compression or swap.

4. 04Step 4 of 7

   Step 4. Read its row in Processes

   The table is sorted by CPU / core, highest first. This column counts 100% as one fully busy core, so 212% means the app is keeping a little more than two cores busy. The Mac as a whole is measured from 0 to 100%, which is why the two numbers look so different.

   Processes

   Apps & helpersAll processesProcess treeProjectsSearch or jump to…⌘KPauseRecord

   LiveRows sampled 10:42:18

   Lumen Edit leads CPU in this sample.

   GPU time sampled 10:42:14 · every 5sNetwork sampled 10:42:13 · Includes local and VPN traffic

   Top CPU / core

   212.4%

   Lumen Edit · 6 processes

   100% = one core

   Top GPU time

   46.2%

   Lumen Edit · 6 processes

   not device GPU %

   Top memory

   6.8GB

   Lumen Edit · 6 processes

   can overlap shared pages

   Unavailable

   3processes

   no memory or disk reading

   shown as —, never as zero

   My processesPinnedName, PID, owner, or path

   Columns & Views312 workloads from 486 processes

   Mac CPU charts are 0–100% of the whole Mac. CPU / core uses 100% for one core. GPU time is not device GPU %. Network columns include local and VPN traffic. — means no reading. * is a partial total.

   NameCPU / coreGPU timeMemoryDisk readDisk writeReceived/sSent/sProcesses

   LLumen Edit212.4%46.2%6.8 GB6.2 MB/s12.2 MB/s0 B/s0 B/s6

   KKite Browser38.6%6.1%4.2 GB36 KB/s84 KB/s1.4 MB/s86 KB/s23

   FForge IDE24.9%1.2%3.1 GB1.4 MB/s820 KB/s12 KB/s4 KB/s14

   HHarbor18.2%0.0%5.6 GB210 KB/s430 KB/s220 KB/s180 KB/s9

   WindowServer11.4%14.8%1.2 GB0 B/s0 B/s0 B/s0 B/s1

   RRoundtable9.8%8.4%920 MB0 B/s24 KB/s310 KB/s290 KB/s5

   NNorthwind Sync6.1%0.0%410 MB3.9 MB/s700 KB/s64 KB/s1.1 MB/s3

   kernel_task4.2%—2.4 GB——0 B/s0 B/s1

   TTessel Design3.7%2.6%1.9 GB0 B/s0 B/s2 KB/s1 KB/s4

   mds_stores2.9%—380 MB940 KB/s260 KB/s0 B/s0 B/s1

   TTempo Player1.8%0.4%340 MB0 B/s0 B/s96 KB/s2 KB/s2

   BBrightline Mail1.1%0.0%520 MB2 KB/s6 KB/s6 KB/s3 KB/s3

   QQuill Notes0.6%0.0%290 MB0 B/s0 B/s0 B/s0 B/s2

   Finder0.4%0.0%210 MB0 B/s0 B/s0 B/s0 B/s1

   Control Center0.3%0.1%148 MB0 B/s0 B/s0 B/s0 B/s1

   Dock0.3%0.0%112 MB0 B/s0 B/s0 B/s0 B/s1

   coreaudiod0.2%—46 MB0 B/s0 B/s0 B/s0 B/s1

   launchd0.2%—28 MB0 B/s0 B/s0 B/s0 B/s1

   bluetoothd0.1%—34 MB0 B/s0 B/s0 B/s0 B/s1

   loginwindow0.1%0.0%71 MB0 B/s0 B/s0 B/s0 B/s1

   L

   Lumen Edit6 processes · sam

   212.4%CPU / core

   CPU / core100% = one core · 60 s

   250%

   Memoryfootprint · 60 s6.8 GB

   8 GB

   60 s agonow

   Ownersam

   Parentlaunchd (1)

   Threads148

   CPU cores occupied2.12

   Physical footprint6.8 GB

   Resident memory7.4 GB

   Member processes · 6Sorted by CPU

   Lumen ExportPID 6347 · 148.6% · 2.9 GB

   Lumen RendererPID 4831 · 38.2% · 1.6 GB

   Lumen EditPID 4812 · 14.7% · 1.2 GB

   Lumen Media ReaderPID 4840 · 8.3% · 640 MB

   Lumen GPU HelperPID 4826 · 2.4% · 310 MB

   Lumen AutosavePID 4853 · 0.2% · 150 MB

   Inspect Application…View History

   PinPauseQuit…Force Quit…

5. 05Step 5 of 7

   Step 5. Tell a spike from a habit

   Beside the table, the inspector draws the last 60 seconds of CPU and memory for the selected app. A single bump is a spike. A line that stays high is sustained work.

   Further down are its member processes, sorted by CPU, so you can see whether one helper is doing all of it.

   Processes

   Apps & helpersAll processesProcess treeProjectsSearch or jump to…⌘KPauseRecord

   LiveRows sampled 10:42:18

   Lumen Edit leads CPU in this sample.

   GPU time sampled 10:42:14 · every 5sNetwork sampled 10:42:13 · Includes local and VPN traffic

   Top CPU / core

   212.4%

   Lumen Edit · 6 processes

   100% = one core

   Top GPU time

   46.2%

   Lumen Edit · 6 processes

   not device GPU %

   Top memory

   6.8GB

   Lumen Edit · 6 processes

   can overlap shared pages

   Unavailable

   3processes

   no memory or disk reading

   shown as —, never as zero

   My processesPinnedName, PID, owner, or path

   Columns & Views312 workloads from 486 processes

   Mac CPU charts are 0–100% of the whole Mac. CPU / core uses 100% for one core. GPU time is not device GPU %. Network columns include local and VPN traffic. — means no reading. * is a partial total.

   NameCPU / coreGPU timeMemoryDisk readDisk writeReceived/sSent/sProcesses

   LLumen Edit212.4%46.2%6.8 GB6.2 MB/s12.2 MB/s0 B/s0 B/s6

   KKite Browser38.6%6.1%4.2 GB36 KB/s84 KB/s1.4 MB/s86 KB/s23

   FForge IDE24.9%1.2%3.1 GB1.4 MB/s820 KB/s12 KB/s4 KB/s14

   HHarbor18.2%0.0%5.6 GB210 KB/s430 KB/s220 KB/s180 KB/s9

   WindowServer11.4%14.8%1.2 GB0 B/s0 B/s0 B/s0 B/s1

   RRoundtable9.8%8.4%920 MB0 B/s24 KB/s310 KB/s290 KB/s5

   NNorthwind Sync6.1%0.0%410 MB3.9 MB/s700 KB/s64 KB/s1.1 MB/s3

   kernel_task4.2%—2.4 GB——0 B/s0 B/s1

   TTessel Design3.7%2.6%1.9 GB0 B/s0 B/s2 KB/s1 KB/s4

   mds_stores2.9%—380 MB940 KB/s260 KB/s0 B/s0 B/s1

   TTempo Player1.8%0.4%340 MB0 B/s0 B/s96 KB/s2 KB/s2

   BBrightline Mail1.1%0.0%520 MB2 KB/s6 KB/s6 KB/s3 KB/s3

   QQuill Notes0.6%0.0%290 MB0 B/s0 B/s0 B/s0 B/s2

   Finder0.4%0.0%210 MB0 B/s0 B/s0 B/s0 B/s1

   Control Center0.3%0.1%148 MB0 B/s0 B/s0 B/s0 B/s1

   Dock0.3%0.0%112 MB0 B/s0 B/s0 B/s0 B/s1

   coreaudiod0.2%—46 MB0 B/s0 B/s0 B/s0 B/s1

   launchd0.2%—28 MB0 B/s0 B/s0 B/s0 B/s1

   bluetoothd0.1%—34 MB0 B/s0 B/s0 B/s0 B/s1

   loginwindow0.1%0.0%71 MB0 B/s0 B/s0 B/s0 B/s1

   L

   Lumen Edit6 processes · sam

   212.4%CPU / core

   CPU / core100% = one core · 60 s

   250%

   Memoryfootprint · 60 s6.8 GB

   8 GB

   60 s agonow

   Ownersam

   Parentlaunchd (1)

   Threads148

   CPU cores occupied2.12

   Physical footprint6.8 GB

   Resident memory7.4 GB

   Member processes · 6Sorted by CPU

   Lumen ExportPID 6347 · 148.6% · 2.9 GB

   Lumen RendererPID 4831 · 38.2% · 1.6 GB

   Lumen EditPID 4812 · 14.7% · 1.2 GB

   Lumen Media ReaderPID 4840 · 8.3% · 640 MB

   Lumen GPU HelperPID 4826 · 2.4% · 310 MB

   Lumen AutosavePID 4853 · 0.2% · 150 MB

   Inspect Application…View History

   PinPauseQuit…Force Quit…

6. 06Step 6 of 7

   Step 6. Find out how long it has been going on

   Click View History at the foot of the inspector. History opens on that app, with every sample of the last minutes. If the app has been busy since you started an export or a build, that is the work you asked for.

   Processes

   Apps & helpersAll processesProcess treeProjectsSearch or jump to…⌘KPauseRecord

   LiveRows sampled 10:42:18

   Lumen Edit leads CPU in this sample.

   GPU time sampled 10:42:14 · every 5sNetwork sampled 10:42:13 · Includes local and VPN traffic

   Top CPU / core

   212.4%

   Lumen Edit · 6 processes

   100% = one core

   Top GPU time

   46.2%

   Lumen Edit · 6 processes

   not device GPU %

   Top memory

   6.8GB

   Lumen Edit · 6 processes

   can overlap shared pages

   Unavailable

   3processes

   no memory or disk reading

   shown as —, never as zero

   My processesPinnedName, PID, owner, or path

   Columns & Views312 workloads from 486 processes

   Mac CPU charts are 0–100% of the whole Mac. CPU / core uses 100% for one core. GPU time is not device GPU %. Network columns include local and VPN traffic. — means no reading. * is a partial total.

   NameCPU / coreGPU timeMemoryDisk readDisk writeReceived/sSent/sProcesses

   LLumen Edit212.4%46.2%6.8 GB6.2 MB/s12.2 MB/s0 B/s0 B/s6

   KKite Browser38.6%6.1%4.2 GB36 KB/s84 KB/s1.4 MB/s86 KB/s23

   FForge IDE24.9%1.2%3.1 GB1.4 MB/s820 KB/s12 KB/s4 KB/s14

   HHarbor18.2%0.0%5.6 GB210 KB/s430 KB/s220 KB/s180 KB/s9

   WindowServer11.4%14.8%1.2 GB0 B/s0 B/s0 B/s0 B/s1

   RRoundtable9.8%8.4%920 MB0 B/s24 KB/s310 KB/s290 KB/s5

   NNorthwind Sync6.1%0.0%410 MB3.9 MB/s700 KB/s64 KB/s1.1 MB/s3

   kernel_task4.2%—2.4 GB——0 B/s0 B/s1

   TTessel Design3.7%2.6%1.9 GB0 B/s0 B/s2 KB/s1 KB/s4

   mds_stores2.9%—380 MB940 KB/s260 KB/s0 B/s0 B/s1

   TTempo Player1.8%0.4%340 MB0 B/s0 B/s96 KB/s2 KB/s2

   BBrightline Mail1.1%0.0%520 MB2 KB/s6 KB/s6 KB/s3 KB/s3

   QQuill Notes0.6%0.0%290 MB0 B/s0 B/s0 B/s0 B/s2

   Finder0.4%0.0%210 MB0 B/s0 B/s0 B/s0 B/s1

   Control Center0.3%0.1%148 MB0 B/s0 B/s0 B/s0 B/s1

   Dock0.3%0.0%112 MB0 B/s0 B/s0 B/s0 B/s1

   coreaudiod0.2%—46 MB0 B/s0 B/s0 B/s0 B/s1

   launchd0.2%—28 MB0 B/s0 B/s0 B/s0 B/s1

   bluetoothd0.1%—34 MB0 B/s0 B/s0 B/s0 B/s1

   loginwindow0.1%0.0%71 MB0 B/s0 B/s0 B/s0 B/s1

   L

   Lumen Edit6 processes · sam

   212.4%CPU / core

   CPU / core100% = one core · 60 s

   250%

   Memoryfootprint · 60 s6.8 GB

   8 GB

   60 s agonow

   Ownersam

   Parentlaunchd (1)

   Threads148

   CPU cores occupied2.12

   Physical footprint6.8 GB

   Resident memory7.4 GB

   Member processes · 6Sorted by CPU

   Lumen ExportPID 6347 · 148.6% · 2.9 GB

   Lumen RendererPID 4831 · 38.2% · 1.6 GB

   Lumen EditPID 4812 · 14.7% · 1.2 GB

   Lumen Media ReaderPID 4840 · 8.3% · 640 MB

   Lumen GPU HelperPID 4826 · 2.4% · 310 MB

   Lumen AutosavePID 4853 · 0.2% · 150 MB

   Inspect Application…View History

   PinPauseQuit…Force Quit…

7. 07Step 7 of 7

   Step 7. Decide

   You now know which app it is, how much it is using and for how long. There are three sensible things to do:

   • Let it finish, if it is doing work you started.
   • Stop it, if it is stuck. See Stop a runaway process safely.
   • Catch it in the act, if it keeps coming back. See Record a slowdown and compare.