Task Manager can set CPU affinity and priority for a running process, but those settings evaporate the moment the process closes. Process Lasso by Bitsum makes these changes persistent and adds an intelligent automation layer called ProBalance that actively manages CPU resources in real time. For gamers and content creators alike, it is one of the most practical system tools available.
What Is Process Lasso?
Process Lasso is a Windows process automation and CPU optimization utility. The free version covers the most important features; Process Lasso Pro adds advanced automation rules and premium support. Key capabilities include:
- ProBalance: Dynamically lowers the priority of background processes that are competing for CPU time during gaming or high-load workloads
- Persistent CPU affinity: Assign specific CPU cores to specific processes permanently
- Persistent priority classes: Set processes to always run at High, Above Normal, Normal, Below Normal, or Idle priority
- Gaming Mode: Temporarily suspends or deprioritizes non-essential background processes
- I/O Priority: Set disk I/O priority per process
- Instance balancer: Prevent more than N instances of a process from running
Download Process Lasso from bitsum.com. The installer includes the ProBalance service that runs in the background even without the GUI open.
Understanding ProBalance
ProBalance is Process Lasso’s flagship feature. It monitors all running processes and identifies ones consuming disproportionate CPU time during periods of high load. When it detects a background process spiking (like an antivirus scan, Windows Update, or a browser tab gone rogue), ProBalance temporarily reduces that process’s priority class to give your foreground application — the game or render — priority access to the CPU.
ProBalance is rule-based and temporary: it does not permanently change priority. When the offending process calms down, ProBalance restores its original priority. This is smarter than just blanket-lowering all background processes permanently.
Configuring ProBalance
In the Process Lasso GUI, go to Options > ProBalance. Key settings:
| Setting | Recommendation |
|---|---|
| Enable ProBalance | On |
| Restraint sensitivity | Medium (adjust down if too aggressive) |
| Exclude foreground applications | On — never restrain your active game |
| Log all restraints | On — useful for diagnosing what was being throttled |
You can also right-click any process in the list and add it to the ProBalance exclusions if it is getting incorrectly throttled (common with audio drivers and system services).
Setting Persistent CPU Affinities
CPU affinity controls which cores a process is allowed to use. This is useful for several scenarios:
- Pinning your game to performance cores: On Intel 12th gen and newer (hybrid architecture), you may want your game to stay on P-cores rather than occasionally being scheduled onto E-cores
- Isolating a streaming encoder: Pin OBS or FFmpeg to specific cores so encoding does not compete with the game on the same cores
- Content creation: Pin rendering background tasks to specific core groups
How to Set It
- Right-click any running process in Process Lasso’s main list
- Go to CPU Affinity > Always > Select CPU Affinity
- Check only the cores you want the process to use
- Click OK
The Always submenu is the key — it saves this affinity rule to Process Lasso’s database, applying it every time that process starts, even after reboots.
For Intel 12th/13th/14th gen CPUs, identify your P-cores (cores 0 through N-1) and E-cores using HWiNFO64 or CPU-Z. Typically, P-cores are cores 0–7 (or 0–5 on a 12-core model) and E-cores follow.
Gaming Mode
Process Lasso’s Gaming Mode is activated by clicking the controller icon in the toolbar or via the tray menu. When active, it:
- Sets the foreground game process to High CPU priority
- Optionally excludes background processes from specific CPU cores (core exclusion)
- Suppresses Windows maintenance tasks
Core exclusion is the most powerful Gaming Mode feature. Enable it via Options > Gaming Mode > CPU Core Exclusion. Select one or two cores to be excluded from all background processes. Those cores become exclusively available for your game’s threads. On a 12-core CPU, excluding cores 10 and 11 from background processes while your game uses all 12 is a common setup.
I/O Priority Settings
Disk I/O priority is separate from CPU priority but equally important during concurrent workloads. Set I/O priority by right-clicking a process and choosing I/O Priority > Always.
| Priority Level | Best For |
|---|---|
| High | Your game or foreground application |
| Normal | Default for most processes |
| Low | Background indexing (SearchIndexer), defrag, backups |
| Very Low | Windows Update downloads during gaming sessions |
Setting MsMpEng.exe (Windows Defender) to Low I/O priority is one of the most impactful changes for users who run Defender scans in the background — it prevents scan activity from causing storage latency during gameplay.
Process Lasso vs Manual Task Manager
| Feature | Task Manager | Process Lasso |
|---|---|---|
| Set CPU affinity | Yes (temporary) | Yes (persistent) |
| Set priority | Yes (temporary) | Yes (persistent) |
| ProBalance automation | No | Yes |
| Per-process I/O priority | No | Yes |
| Gaming Mode | No | Yes |
| Rules survive reboot | No | Yes |
| Automation rules | No | Yes (Pro) |
The core advantage of Process Lasso is persistence and automation. Every setting you make in Task Manager resets when the process exits. Everything in Process Lasso is remembered.
Use Cases by Workload
Gaming
- Enable Gaming Mode
- Set game executable to High priority (persistent)
- Set MsMpEng.exe and SearchIndexer.exe to Low I/O priority
- Enable core exclusion for 1–2 cores on CPUs with 10+ cores
Content Creation (Video Rendering)
- Set your render application (DaVinci Resolve, Premiere Pro, Blender) to High CPU priority
- Pin background encoding jobs to E-cores (on hybrid Intel CPUs) to keep P-cores for the primary render
- Set cloud sync apps (OneDrive, Dropbox) to Very Low I/O priority
Streaming While Gaming
- Pin OBS to a specific core group separate from your game
- Set OBS encoder threads affinity to match (OBS > Settings > Advanced > Process Priority)
- Enable ProBalance with moderate sensitivity
Process Lasso is a $35 value in its Pro form but the free version covers everything above. For users who are serious about CPU performance, it is one of the most impactful tools available without touching overclocking.