mine, all mine! You can’t have them. Agenda 1. Current status of C++ safety: MISRA and C++ CG 2. Parallel Safety rules 3. Automotive Safety case Safety Critical API Evolution minimize API surface area no harm What is still missing? So far most only deal with Sequential code Very few deal with Parallel code Even fewer deal with Concurrent, event driven code None deal with Heterogeneous dispatch rules pulled from • C++CG • HIC++ • REphrase H2020 project • CERT C++ • JSF++ (no parallel rules) • WG23 (no parallel rules) • Added some from our own contributions • Many joined, average 5-8 per meeting

programs using parallel algorithms and executors Mark Hoemmen* mhoemmen@stellarscience.com CppCon 2020 * hoʊ’mən, or hœm’mən; he/himWho am I? • > 10 years post-PhD experience writing parallel C++ for for science and engineering • Background: Parallel algorithms for big linear algebra problems • 1st WG21: Nov 2017 • Started new job at Stellar Science in March Eschew raw pointersOutline • Parallelism Parallelism makes error handling harder… • …C++ parallel algorithms and tasks specifically • Message Passing Interface (MPI): 3 decades of distributed-memory parallel programming • MPI teaches design patterns

std::simd how to express inherent parallelism efficiently via data-parallel types Dr. Matthias Kretz GSI Helmholtz Center for Heavy Ion Research CppCon ’23 @mkretz@floss.social github.com/mattkretzMotivation g++ -O3 -DNDEBUG -march=native scalar 0.25 FLOP/cycle 0.5 FLOP/cycle data-parallel 8 FLOP/cycle 64 FLOP/cycle A data-parallel type wider than the default can increase ILP! 64 0.25 = 256 times faster g++ -O3 -DNDEBUG -march=native scalar 0.25 FLOP/cycle 0.5 FLOP/cycle data-parallel 8 FLOP/cycle 64 FLOP/cycle A data-parallel type wider than the default can increase ILP! 64 0.25 = 256 times faster

Commands 135 Database Maintenance 136 System Functions, Catalog Tables and Views 137 Greenplum Query Optimizer (GPORCA) 138 Append-Optimized Tables 138 Performance 139 Removed Features 139 Deprecated Transactions 174 Managing XIDs and the Frozen XID 175 Example of XID Modulo Calculations 176 About Parallel Data Loading 177 About Redundancy and Failover in Greenplum Database 178 About Segment Mirroring 357 Viewing a Classic Syntax Sub-Partition Template 358 Constructing a pg_partitions-Equivalent Query 358 About Partition Pruning 358 Partition Maintenance 360 Partition Maintenance with the Modern

6.27.1 143 New and Changed Features 143 Server 143 Query Processing 144 Release 6.27.0 144 Features 144 Resolved Issues 145 Server 145 Query Processing 146 Database Utilities 146 Cluster Management Release 6.26 146 Release 6.26.4 146 Server 147 Query Processing 147 Release 6.26.3 147 Server 147 Release 6.26.2 147 New Features 148 Query Processing 148 Server 148 Cluster Management 148 Zstandard (zstd) Supported Version 149 Query Processing 149 Server 149 Cluster Management 150 Release 6.26.0 150 Features 150 Resolved Issues 150 Server 151 Query Processing 151 Cluster Management

Notes 139 Upgrading Greenplum 139 Release 6.25 139 Release 6.25.3 139 Cluster Management 139 Query Processing 139 Server 140 Disaster Recovery 140 Release 6.25.2 140 New and Changed Features 140 143 Query Processing 143 Release 6.25.1 143 Server 143 Data Flow 144 Release 6.25.0 144 Features 144 Resolved Issues 145 Server 145 VMware Greenplum 6 Documentation VMware, Inc. 3 Query Processing Release 6.24.6 146 Query Processing 146 Server 147 Release 6.24.5 147 Data Flow 147 Release 6.24.4 147 Changed Features 147 Resolved Issues 147 Server 147 Cluster Management 148 Query Processing 148

Resolved Issues 135 Server 135 Query Processing 136 Cluster Management 136 Extensions 136 Other 136 Release 6.22 137 Release 6.22.2 137 Resolved Issues 137 Server 137 Query Processing 138 Data Flow Server 139 Query Processing 139 Cluster Management 140 Release 6.22.0 140 Features 140 Resolved Issues 142 Server 142 VMware Tanzu Greenplum 6 Documentation VMware, Inc 3 Query Processing 143 21.3 144 Server 144 Release 6.21.2 144 Server 144 Query Processing 145 Release 6.21.1 145 Features 145 Resolved Issues 145 Server 145 Query Processing 146 Data Flow 147 Tanzu Greenplum on vSphere

Server 134 Query Processing 135 Data Flow 135 Cluster Management 136 Release 6.23 136 Release 6.23.3 136 Changed Feature 136 Resolved Issues 136 Extensions 136 Server 136 Query Processing 137 Issues 138 Server 138 Query Processing 140 Data Flow 140 VMware Greenplum 6 Documentation VMware, Inc 3 Release 6.23.0 140 Features 140 Resolved Issues 142 Server 142 Query Processing 143 Cluster Release 6.22.2 144 Resolved Issues 144 Server 144 Query Processing 145 Data Flow 146 Release 6.22.1 146 Resolved Issues 146 Server 146 Query Processing 147 Cluster Management 147 Release 6.22

129 Release 6.21 129 Release 6.21.2 129 Server 129 Query Processing 129 Release 6.21.1 129 Features 129 Resolved Issues 130 Server 130 Query Processing 131 Data Flow 131 Tanzu Greenplum on vSphere Resolved Issues 133 Server 133 Query Processing 135 Cluster Management 135 Data Flow 135 Extensions 136 Release 6.20 136 Release 6.20.5 136 Resolved Issues 136 Query Optimizer 136 Server 136 VMware 137 Server 137 Cluster Management 137 Query Optimizer 137 Data Flow 137 Release 6.20.1 138 Resolved Issues 138 Server 138 Cluster Management 138 Query Optimizer 138 Release 6.20.0 139 Features

Release 6.22.2 134 Resolved Issues 134 Server 135 Query Processing 136 Data Flow 136 Release 6.22.1 136 Resolved Issues 136 Server 137 Query Processing 137 Cluster Management 138 Release 6.22 22.0 138 Features 138 Resolved Issues 140 Server 140 Query Processing 141 Data Flow 141 Cluster Management 141 DataDirect ODBC 141 Release 6.21 142 VMware Tanzu Greenplum 6 Documentation VMware 21.3 142 Server 142 Release 6.21.2 142 Server 142 Query Processing 142 Release 6.21.1 142 Features 142 Resolved Issues 142 Server 142 Query Processing 144 Data Flow 144 Tanzu Greenplum on vSphere