2.1 The IBM POWER9 processor2.1.1 POWER9 processor overview2.1.2 POWER9 processor features2.1.3 POWER9 processor core2.1.4 Simultaneous multithreading2.1.5 Processor feature codes2.1.6 Memory access2.1.7 On-chip L3 cache innovation and intelligent caching2.1.8 Hardware transactional memory2.1.9 Coherent Accelerator Processor Interface 2.02.1.10 Power management and system performance2.1.11 Comparison of the POWER9, POWER8, and POWER7+ processors2.2 Memory subsystem2.2.1 Memory placement rules2.2.2 Memory bandwidth2.3 System bus2.4 Internal I/O subsystem2.4.1 Slot configuration2.4.2 System ports2.5 Peripheral Component Interconnect adapters2.5.1 Peripheral Component Interconnect Express2.5.2 LAN adapters2.5.3 Graphics accelerator adapters2.5.4 SAS adapters2.5.5 Fibre Channel adapters2.5.6 InfiniBand host channel adapter2.5.7 Cryptographic coprocessor2.5.8 Coherent Accelerator Processor Interface adapters2.5.9 USB adapters2.6 Internal storage2.6.1 Backplane (#EJ1C)2.6.2 Split backplane option (#EJ1E)2.6.3 Backplane (#EJ1D)2.6.4 Expanded Function Backplane (#EJ1M)2.6.5 NVMe support2.6.6 Backplane (#EJ1F)2.6.7 Expanded Function Storage Backplane (#EJ1G)2.6.8 RAID support2.6.9 Easy Tier2.6.10 External SAS ports2.6.11 Media drawers2.6.12 External DVD drives2.6.13 RDX removable disk drives2.7 External IO subsystems2.7.1 Peripheral Component Interconnect Express Gen3 I/O expansion drawer2.7.2 PCIe Gen3 I/O expansion drawer optical cabling2.7.3 PCIe Gen3 I/O expansion drawer system power control network cabling2.8 External disk subsystems2.8.1 EXP24SX SAS Storage Enclosure and EXP12SX SAS Storage Enclosure2.8.2 IBM Storage2.9 Operating system support2.9.1 AIX operating system2.9.2 IBM i2.9.3 Linux operating system2.9.4 Virtual I/O Server2.10 POWER9 reliability, availability, and serviceability capabilities2.11 Manageability2.11.1 Service user interfaces2.11.2 IBM Power Systems Firmware maintenance2.11.3 Concurrent firmware maintenance improvements2.11.4 Electronic Services and Electronic Service Agent