Install l/Activity and take a first look

Steps

1. 01Step 1 of 8

   Step 1. Download the disk image

   Get the current version from the download page. The file is about 12 MB and its name ends in .dmg. Open it from your Downloads folder.

2. 02Step 2 of 8

   Step 2. Drag the app into Applications

   A small window opens with the app on the left and your Applications folder on the right. Drag l/Activity onto Applications. Then eject the disk image and open the app from Applications or Launchpad.

   Finder shows the app as l/Activity. On disk it is called Activity.app, because a file name cannot contain a slash.

   l/Activity

   l/Activity

   Applications

3. 03Step 3 of 8

   Step 3. Let the first launch check its version

   The first time it opens, l/Activity shows Verifying this version for a moment. It is checking a signed statement from lslash.app that this build is current. This needs a connection once.

   After a successful check the app works offline for up to seven days at a time. You can read more about this in the FAQ.

4. 04Step 4 of 8

   Step 4. Find your way around the sidebar

   The sidebar has four groups, and they are the whole app:

   • Monitor is what your Mac is doing now. Each row shows its own live reading.
   • Investigate is what it did earlier: History, Sessions and Diagnostics.
   • Files & Apps is disk space: Storage, Locate, Duplicates and Apps.
   • This Mac holds four small tools: Mac Care, App Volume, Keep Awake and Menu Bar.

   The switch beside Monitor turns all measuring on or 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.

5. 05Step 5 of 8

   Step 5. Read the stage

   Every page opens with a stage. On the left is one sentence built from the reading on screen. Beside it is the page's main instrument.

   On Overview the instrument is a map of your chip: a cell for every CPU core, the GPU, the Neural Engine, the memory they share and the power they draw, with disk and network beside it. Click any tile to open its page.

   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.

6. 06Step 6 of 8

   Step 6. Know the controls that are on every page

   The title bar is the same everywhere. Search or jump to… (⌘K) opens any page or command by name. Pause freezes the readings on screen. Record starts a recording you can replay later. The last two buttons refresh the page and export a snapshot.

   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.

7. 07Step 7 of 8

   Step 7. Glance at the bottom edge

   The strip along the bottom is called the deck. The left side says how readings are being collected, for example Live · every 2s. The right side shows what l/Activity itself is busy with: a recording, Keep Awake, or a disk scan under Activity.

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

   SummaryDashboardSearch or jump to…⌘KPauseStop

   Rec00:01:2442 samples · system 2s

   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

   Recording to SessionsStop with ⇧⌘R

   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.

8. 08Step 8 of 8

   Step 8. See which permissions exist, and that you need none yet

   Watching your Mac needs no permission, no password and no extra software. The disk tools ask for access only when you use them.

   To see every permission in one place, choose Help → Setup on This Mac…. It opens Settings on the Permissions page.

   SettingsMake l/Activity work the way you do.

   Search or jump to…⌘K

   Search settings

   GeneralDark · Dock and menu bar

   PermissionsFinder not requested

   MonitoringEvery 2 seconds

   History & Recording30 min live · 24 h max

   Storage & CacheEvery hour · 1.8 GB

   AlertsNotifications off

   About & PrivacyVersion 2.39

   Changes save automatically

   PermissionsReview disk access and app removal permissions.

   Finder Automation and Accessibility refresh automatically when you open this page or return to l/Activity. Folder access is checked when requested. Ordinary monitoring needs none of these permissions.

   For disk scans

   Full Disk Access

   Check in System Settings

   Allows Storage to inspect protected locations and find more related app data. A fan controller working from a protected folder such as Desktop may also require this access.

   Open Full Disk AccessReveal App

   Files & Folders

   Observed folder access

   Check all folder access

   Desktop/Users/sam/Desktop

   ReadableRecheck

   l/Activity could read this folder's directory listing. This does not check its children, file contents, removal rights, or Full Disk Access.

   Checked 13 Oct 2026 at 10:38:07

   Documents/Users/sam/Documents

   Not checkedCheck

   Downloads/Users/sam/Downloads

   Not checkedCheck

   l/Activity folder/Users/sam/Library/Application Support/app.activity.desktop

   Not checkedCheck

   Choose Folder to Check…Files & Folders Settings

   For App Volume

   System Audio Recording

   Check in System Settings

   Temporary per-app volume control needs access to that app’s audio. macOS does not provide a reliable public audio-only permission status check.

   Open Audio PermissionsReveal App

   For cleanup and app removal

   Finder Automation

   Not requested

   Lets l/Activity ask Finder to move your confirmed selections to recoverable Trash. Finder can ask for an administrator password when necessary.

   Finder automation needs your consent. Request Access to let macOS ask; no files will be moved.

   Request Finder Access…Automation SettingsRecheck

   Status refreshes automatically when this page opens or l/Activity becomes active. If access was denied, enable l/Activity → Finder in Automation. Requesting access does not remove any files.

   Checked 13 Oct 2026 at 10:41:52

   App Management

   Check in System Settings

   macOS may require this permission when changing or removing other applications.

   macOS does not provide a public status query for App Management. Review l/Activity in System Settings → Privacy & Security → App Management. Access is checked again when you confirm an app removal.

   Open App ManagementReveal App

   Administrator authorization

   Asked when needed

   An administrator password is authorization for a particular operation, not a permanent permission switch.

   Move to Trash lets Finder request authorization when needed. Delete Permanently uses your current permissions. Full Disk Access does not override file ownership, system protection or a read-only volume.

   l/Activity runs as your user. The optional power capture in Hardware separately asks for one read-only administrator-authorized sample.