Excel Performance Problems

How to Fix Excel Solver High Memory Usage on M3 MacBook Pro

Natalie Taylor Sep 28, 2026 869 views

Question details

The user is experiencing excessive memory consumption and stalling when running complex models with Excel Solver on an M3 MacBook Pro.

How to Fix Excel Solver High Memory Usage on M3 MacBook Pro

Product: Microsoft Excel
Device & OS: Mac (Apple Silicon M3)
Scenario: Running complex data models and calculations using the Excel Solver add-in.
Observed behavior: Excel Solver consumes a rapidly growing amount of pseudo-virtual memory (often reported above 100 GB in Activity Monitor) or stalls completely, despite running on modern Apple Silicon hardware.

Before you start

Ensure you have updated macOS to the latest version and saved a backup copy of your complex workbook before altering constraints or calculation settings.

Solution 1Recommended

Enable Multithreaded Calculation

Maximize the use of your M3 chip's performance by allowing Excel to use all available processors.

By default, Excel might not be utilizing all the processing cores available on your M3 MacBook Pro. Enabling multithreaded calculations ensures the workload is distributed efficiently, preventing stalls during heavy Solver tasks.

Open Excel Preferences

Launch Microsoft Excel on your Mac, click on 'Excel' in the top Apple menu bar, and select 'Preferences'.

Access Calculation Settings

In the Preferences window, locate and click on 'Calculation'.

Enable Multithreading

Check the box for 'Enable multi-threaded calculation' and ensure that the option is set to use the maximum number of processors available.

Performance Boost: Allowing maximum processors helps Solver complete complex models significantly faster without bottlenecking a single CPU core.

Solution 2

Optimize Workbook Constraints and Formulas

Reduce the calculation load on the Solver by simplifying your mathematical model and removing volatile functions.

Solution 3

Check Memory Mapping and Update Excel

Determine if the high memory reading is virtual or physical, and install updates to patch known Apple Silicon memory leaks.

Free Microsoft Office alternative

Switch to WPS Office for Efficient Spreadsheet Processing

If Microsoft Excel continues to consume excessive memory or stall during complex calculations on your Mac, consider switching to WPS Office. It provides a highly compatible alternative designed to handle datasets smoothly without overloading your system resources.

1. Download WPS Office: Visit the official WPS website and download the Mac version of WPS Office.
2. Install the Software: Open the downloaded installer package and follow the on-screen instructions to set up WPS Office on your Mac.
3. Open Your Workbook: Launch WPS Spreadsheet and open your existing complex workbooks directly to continue your analysis smoothly.

Free and lightweight, consuming significantly less RAM and storage spaceHighly compatible with Microsoft Excel formats including .xlsx, .xls, and .csvFamiliar user interface allowing a seamless transition without a learning curveStable performance optimized for both Intel and Apple Silicon Macs

microsoft office alternative - wps office

Frequently Asked Questions

Why does Activity Monitor show Excel using over 100 GB of memory on my Mac?

Extremely high memory readings usually represent virtual memory (or pseudo-virtual memory) dynamically allocated by macOS, rather than actual physical RAM consumption. It reflects how the application requests memory address space, which is common in complex modeling, rather than a crash-inducing physical memory limit.

Does upgrading to an M3 MacBook Pro improve Excel Solver speed?

Yes, the M3 processor is exceptionally fast and generally reduces calculation times. However, if your model is very large and you upgraded from an older machine with 32 GB of RAM to an M3 with 18 GB, Excel might rely slightly more on swap memory. Enabling multithreaded calculation usually bridges this gap.

What are volatile formulas and how do they impact Excel Solver?

Volatile formulas, such as NOW, TODAY, OFFSET, and INDIRECT, trigger a recalculation every time a change is made anywhere in the workbook. When running Solver, this forces Excel to process massive amounts of unnecessary computations iteratively, heavily increasing memory usage and processing time.

Can excessive constraints cause Excel Solver to stall?

Yes, an overly complex model with too many rigid or redundant constraints can cause Solver to stall or run out of usable resources while searching for a solution. Simplifying constraints and testing a scaled-down model is the best way to resolve this.

Excel & Data Problems