Introduce ngt::AnyBuffer

[fwyzard]

PR description:

ngt::AnyBuffer behaves like std::any, with two differences: it can only be used with trivially copyable types, and provides access to the underlying memory buffer to allow memcpy'ing its content.

[fwyzard]

please test

[cmsbuild]

cms-bot internal usage

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-49235/46582

• There are other open Pull requests which might conflict with changes you have proposed:
  • File DataFormats/Common/interface/AnyBuffer.h modified in PR(s): Extend CMSSW to a distributed application over MPI #32632, Implement a GenericCloner test module #47504, Implement a GenericCloner test module based on an edmplugin::PluginFactory #49152, Enabling usage of filters in MPI offloading #49233

[cmsbuild]

A new Pull Request was created by @fwyzard for master.

It involves the following packages:

• DataFormats/Common (core)

@Dr15Jones, @makortel, @smuzaffar can you please review it and eventually sign? Thanks.
@makortel, @missirol, @mmusich, @rovere, @wddgit this is something you requested to watch as well.
@ftenchini, @mandrenguyen, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

[fwyzard]

@makortel @Dr15Jones the use case for edm::AnyBuffer is for sending small, trivially copyable objects over a serialisation/deserialisation chain (e.g. like MPI_Send/MPI_Recv) whenthe sender and receiver know the concrete type, but the code doing the send and receive does not.

Examples are the various variations of adding MPI support to CMSSW in #32632 or #49233, and the stand-alone tests in #47504 or #49152.

[fwyzard]

type ngt

[cmsbuild]

+1

Size: This PR adds an extra 28KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-60ef34/48869/summary.html
COMMIT: 846c960
CMSSW: CMSSW_16_0_X_2025-10-28-1100/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/49235/48869/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 6 differences found in the comparisons
• DQMHistoTests: Total files compared: 51
• DQMHistoTests: Total histograms compared: 3939953
• DQMHistoTests: Total failures: 32
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3939901
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 50 files compared)
• Checked 218 log files, 188 edm output root files, 51 DQM output files
• TriggerResults: no differences found

[makortel]

Examples are the various variations of adding MPI support to CMSSW in #32632 or #49233, and the stand-alone tests in #47504 or #49152.

While this PR looks seemingly straightforward, I want to understand the wider context (again) first before commenting (especially #49152). It will probably take me something along a week or two to have a good moment to start digesting them.

[fwyzard]

OK, understood, though we would appreciate not having to rebuild about 1000 packages every time 🤷🏻‍♂️

[mandrenguyen]

+1

[fwyzard]

Will be moved to ngt::AnyBuffer under HeterogeneousCore/SerialisationCore.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-49235/46993

• There are other open Pull requests which might conflict with changes you have proposed:
  • File HeterogeneousCore/SerialisationCore/README.md modified in PR(s): Trivial serialisation plugin mechanism #49475
  • File HeterogeneousCore/SerialisationCore/interface/AnyBuffer.h modified in PR(s): Trivial serialisation plugin mechanism #49475

[cmsbuild]

Pull request #49235 was updated. @cmsbuild can you please check and sign again.

[fwyzard]

@cms-sw/core-l2 we are still thinking about the new package name, but let me know if you would prefer to have this under FWCore and in the edm namespace.

[fwyzard]

please test

[cmsbuild]

+1

Size: This PR adds an extra 20KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-60ef34/49710/summary.html
COMMIT: b0f1776
CMSSW: CMSSW_16_0_X_2025-11-26-2300/el8_amd64_gcc13
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/49235/49710/install.sh to create a dev area with all the needed externals and cmssw changes.

DAS Queries: The DAS query tests failed, see the summary page for details.

Comparison Summary

Summary:

• You potentially added 2 lines to the logs
• ROOTFileChecks: Some differences in event products or their sizes found
• Reco comparison results: 4 differences found in the comparisons
• Reco comparison had 4 failed jobs
• DQMHistoTests: Total files compared: 53
• DQMHistoTests: Total histograms compared: 4269233
• DQMHistoTests: Total failures: 67
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 4269146
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 52 files compared)
• Checked 227 log files, 198 edm output root files, 53 DQM output files
• TriggerResults: no differences found

[fwyzard]

Included in #49475.