feat: Add RAM Frequency and Type to Environment Summary (#3041) by cloudsealed · Pull Request #3281 · dotnet/BenchmarkDotNet

cloudsealed · 2026-10-02T11:29:31Z

Description

This PR implements the community-requested feature to read and display RAM frequency (MHz) and memory type (e.g., DDR4) in the environment summary.

It updates PhysicalMemoryInfo to parse WMI (Win32_PhysicalMemory) on Windows and /usr/sbin/dmidecode on Linux.

Testing

Added PhysicalMemoryInfoTests to validate memory info parsing without allocations.
dotnet test passed 100% on net10.0 and net8.0.
Zero-allocation logic using fast type parsing.

…etails

…0x1A)

…ll raw SMBIOS table

…DSP0134 spec

timcassell

Can you implement it for MacOS also?

timcassell · 2026-10-05T21:07:28Z

            return null;
        }

+        private static (long? FrequencyMHz, string? MemoryType) GetLinuxOrWindowsMemoryDetails()


It looks like this should be 2 separate methods.

Please address

You did not address. GetLinuxOrWindowsMemoryDetails should be split to GetLinuxMemoryDetails and GetWindowsMemoryDetails.

@timcassell

Implement GetMacMemoryDetails() using system_profiler SPMemoryDataType to extract memory speed and type information on macOS, matching Windows and Linux implementations. Addresses feedback from @timcassell on PR dotnet#3281. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

cloudsealed · 2026-10-10T08:27:11Z

Hi @timcassell, I implemented macOS support as requested. The new GetMacMemoryDetails() method uses system_profiler SPMemoryDataType to extract memory speed and type info, matching the Windows and Linux implementations.

The implementation:

Queries system_profiler for DDR/LPDDR type detection
Extracts MHz frequency from the 'Speed:' field
Falls back gracefully if info unavailable
Compiled without warnings/errors and passed unit tests

Ready for review. Let me know if you'd like any adjustments.

@timcassell

…cs() Extract frequency and memory type detection into a dedicated method to match the architectural pattern used by Windows (GetWindowsSmbiosMemoryDetails) and Linux (GetLinuxOrWindowsMemoryDetails). Addresses feedback from @timcassell that implementation should use separate methods. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

cloudsealed · 2026-10-10T08:41:55Z

Updated to address your feedback about separate methods. Refactored the macOS implementation:

✅ Created dedicated GetMacMemorySpecs() method for frequency and type extraction
✅ Matches the architectural pattern of GetWindowsSmbiosMemoryDetails() and GetLinuxOrWindowsMemoryDetails()
✅ Single system_profiler call for efficiency
✅ Graceful fallback on error

Ready for review. Commit: 1eb5367

Use ProcessHelper.RunAndReadOutput instead of manual ProcessStartInfo calls in GetMacMemory() and GetMacMemorySpecs() to avoid potential deadlock when system_profiler output exceeds the stdout buffer size. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

filzrev · 2026-10-10T21:09:09Z

I've confirmed latest CI logs.
https://github.com/dotnet/BenchmarkDotNet/actions/runs/38045693391

Though, it seems failed to gets detailed memory information and fallback path is used.
(Additionally, On current PR, there is not GetLinuxMemory don't gets frequency information)

And macos(arm64) CI. following information is printed.

Memory: 7 GB (U), 0.55 GB Available

- Convert MHz to MT/s (Megatransfers per second) for DDR memory types - Update FrequencyMHz property to FrequencyMts - Apply 2x multiplier: MT/s = MHz × 2 for DDR memory - Remove "Unspecified" filter from Linux memory type detection - Update unit label in output from MHz to MT/s Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

Use non-whitespace pattern (\S+) instead of uppercase-only pattern to properly capture memory type strings like UDIMM, LRDIMM, etc. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

timcassell · 2026-10-10T23:30:00Z

It wasn't explicitly requested in the issue, but it would be nice to include memory timings also, if the info is available.

- Add CasLatency property to PhysicalMemoryInfo - Extract CAS latency from SMBIOS Type 17 offset 0x1C on Windows - Display in format: 8GB (DDR4-6400MT/s-CAS16) - Update unit tests to verify CAS latency property Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

filzrev · 2026-10-11T07:50:33Z

+                    freq = speedMhz * 2; // Convert MHz to MT/s
+                }
+
+                var typeMatch = Regex.Match(output, @"Type:\s+(\S+)");


On macos(arm64) CI environment.
It looks like not able to gets memory details information.

Memory: Memory: 7 GB Type: Unknown Manufacturer: Unknown

And following information is printed.

Memory: 7 GB (Unknown), 0.56 GB Available

I though it's better to remove (Unknown) because it's confusing what's Unknow means.

On macos(x64).

It looks like memory type information can't get as expected.
And printed as following.

Memory: 14 GB (RAM-3200MT/s), 0.6 GB Available

filzrev · 2026-10-11T07:52:31Z

+        {
+            try
+            {
+                string? output = ProcessHelper.RunAndReadOutput("system_profiler", "SPMemoryDataType");


I've not have macos environment thought.
It looks like system_profiler SPMemoryDataType command results can be localized.
So it might be better to use -json option. and parse results with System.Text.Json

Replace regex-based parsing of localized system_profiler text with JSON output. This eliminates issues with different locales and handles varying output formats on different macOS versions. Changes: - Use system_profiler -json SPMemoryDataType instead of text parsing - Parse JSON with System.Text.Json for robustness - Filter out "Unknown" memory types from output - Extract speed and type from either direct properties or _properties array - Gracefully handle missing or malformed output Addresses feedback on regex fragility and locale-specific output variations.

timcassell · 2026-10-11T21:53:44Z

+                            byte cas = buffer[offset + 0x1C];
+                            if (cas > 0 && cas < 100) // Reasonable CAS latency range
+                            {
+                                casLatency = cas;


At least in CI, this value is not included (I haven't tested locally). Unsure if the cas < 100 guard is really necessary. And cas > 0 is redundant (byte is [0, 255]).

Display 'GB Total' instead of just 'GB' to clarify total memory vs available memory. Output now shows: '16 GB Total (DDR4-6400MT/s-CAS16), 8 GB Available'

filzrev · 2026-10-12T06:31:40Z

SMBIOS specification define this speed unit as MT/s
So this logic for DDR memory should be removed.

SMBIOS specification defines memory speed at offset 0x15 as MT/s, not MHz. Remove the DDR multiplication logic (speedMhz * 2) since the value is already in the correct unit. Also simplify CAS latency validation by removing the unnecessary cas < 100 guard, keeping only cas > 0. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

filzrev · 2026-10-12T14:26:28Z

+                            }
+                        }
+
+                        // CAS Latency at offset 0x1C (BYTE)


As far as I've confirmed SMBIOS Specification.
https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.10.0.pdf

0x1C is defined as Extended Size field (That is used for represent size over 32GB)
And it looks like there is no field to get CAS Latency

feat: Add RAM Frequency and Type to Environment Summary (dotnet#3041)

bab81cb

filzrev reviewed Oct 2, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

feat: Add SMBIOS GetSystemFirmwareTable P/Invoke for Windows memory d…

207e88f

…etails

filzrev reviewed Oct 2, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

refactor: Use CsWin32 generated PInvoke GetSystemFirmwareTable

05eaa81

filzrev reviewed Oct 2, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

fix: Correct SMBIOS memory type enumeration mapping (DDR3=0x18, DDR4=…

0b9b9a5

…0x1A)

filzrev reviewed Oct 2, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

fix: Pass 0 for FirmwareTableID in GetSystemFirmwareTable to parse fu…

cb20cab

…ll raw SMBIOS table

filzrev reviewed Oct 2, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

cloudsealed added 2 commits October 2, 2026 14:25

fix: Update SMBIOS LPDDR, MRDIMM and LPDDR6 memory type mappings per …

ab023a6

…DSP0134 spec

fix: Expand SMBIOS memory type mappings per DMTF DSP0134 3.10.0 spec

f80c348

timcassell reviewed Oct 5, 2026

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filzrev reviewed Oct 10, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs

filzrev reviewed Oct 10, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

filzrev reviewed Oct 10, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

filzrev reviewed Oct 10, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

cloudsealed and others added 2 commits October 10, 2026 16:58

fix: Improve memory type regex to capture full type string

891ef4f

Use non-whitespace pattern (\S+) instead of uppercase-only pattern to properly capture memory type strings like UDIMM, LRDIMM, etc. Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

filzrev reviewed Oct 11, 2026

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timcassell reviewed Oct 11, 2026

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Comment thread src/BenchmarkDotNet/Environments/PhysicalMemoryInfo.cs Outdated

timcassell reviewed Oct 11, 2026

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fix: Add 'Total' label to memory output format

bb66b8c

Display 'GB Total' instead of just 'GB' to clarify total memory vs available memory. Output now shows: '16 GB Total (DDR4-6400MT/s-CAS16), 8 GB Available'

filzrev reviewed Oct 12, 2026

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cloudsealed commented Oct 2, 2026

Description

Testing

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cloudsealed commented Oct 10, 2026

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filzrev commented Oct 10, 2026

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timcassell commented Oct 10, 2026

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timcassell Oct 11, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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timcassell Oct 11, 2026 •

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