#include <metadata_management.h>
Public Attributes | |
| u64 | num_targets |
| int | num_devices |
| u64 | capacities [kMaxDevices] |
| std::atomic< u64 > * | bytes_available |
| Thresholds | bo_capacity_thresholds [kMaxDevices] |
Detailed Description
A snapshot view of the entire system's Targets' available capacities.
This information is only stored on 1 node, designated by MetadataManager::global_system_view_state_node_id, and is only updated by 1 rank (the Hermes process on that node). Hence, it does not need to be stored in shared memory and we are able to use normal std containers. However, since multiple RPC handler threads can potentially update the bytes_available field concurrently, we must not do any operations on the vector itself. We can only do operations on the atomics within. The vector is created in StartGlobalSystemViewStateUpdateThread, and thereafter we can only call functions on the individual atomics (e.g., bytes_available[i].fetch_add), which is thread safe.
Member Data Documentation
◆ num_targets
| u64 hermes::GlobalSystemViewState::num_targets |
The total number of buffering Targets in the system
◆ num_devices
| int hermes::GlobalSystemViewState::num_devices |
The number of devices per node
◆ capacities
| u64 hermes::GlobalSystemViewState::capacities[kMaxDevices] |
capacities of devices
◆ bytes_available
| std::atomic<u64>* hermes::GlobalSystemViewState::bytes_available |
The remaining capacity of each Target in the system
◆ bo_capacity_thresholds
| Thresholds hermes::GlobalSystemViewState::bo_capacity_thresholds[kMaxDevices] |
The min and max capacity thresholds (percentage) for each Target in the system
The documentation for this struct was generated from the following file:
- /home/runner/work/hermes/hermes/src/metadata_management.h
