摘要:
Methods, apparatus, and computer program products are disclosed for executing a gather operation on a parallel computer according to embodiments of the present invention. Embodiments include configuring, by the logical root, a result buffer or the logical root, the result buffer having positions, each position corresponding to a ranked node in the operational group and for storing contribution data gathered from that ranked node. Embodiments also include repeatedly for each position in the result buffer: determining, by each compute node of an operational group, whether the current position in the result buffer corresponds with the rank of the compute node, if the current position in the result buffer corresponds with the rank of the compute node, contributing, by that compute node, the compute node's contribution data, if the current position in the result buffer does not correspond with the rank of the compute node, contributing, by that compute node, a value of zero for the contribution data, and storing, by the logical root in the current position in the result buffer, results of a bitwise OR operation of all the contribution data by all compute nodes of the operational group for the current position, the results received through the global combining network.
摘要:
Performing a deterministic reduction operation in a parallel computer that includes compute nodes, each of which includes computer processors and a CAU (Collectives Acceleration Unit) that couples computer processors to one another for data communications, including organizing processors and a CAU into a branched tree topology in which the CAU is a root and the processors are children; receiving, from each of the processors in any order, dummy contribution data, where each processor is restricted from sending any other data to the root CAU prior to receiving an acknowledgement of receipt from the root CAU; sending, by the root CAU to the processors in the branched tree topology, in a predefined order, acknowledgements of receipt of the dummy contribution data; receiving, by the root CAU from the processors in the predefined order, the processors' contribution data to the reduction operation; and reducing, by the root CAU, the processors' contribution data.
摘要:
A parallel computer that includes compute nodes having computer processors and a CAU (Collectives Acceleration Unit) that couples processors to one another for data communications. In embodiments of the present invention, deterministic reduction operation include: organizing processors of the parallel computer and a CAU into a branched tree topology, where the CAU is a root of the branched tree topology and the processors are children of the root CAU; establishing a receive buffer that includes receive elements associated with processors and configured to store the associated processor's contribution data; receiving, in any order from the processors, each processor's contribution data; tracking receipt of each processor's contribution data; and reducing, the contribution data in a predefined order, only after receipt of contribution data from all processors in the branched tree topology.
摘要:
Compute nodes of a parallel computer organized for collective operations via a network, each compute node having a receive buffer and establishing a topology for the network; selecting a schedule for a broadcast operation; depositing, by a root node of the topology, broadcast data in a target node's receive buffer, including performing a DMA operation with a well-known memory location for the target node's receive buffer; depositing, by the root node in a memory region designated for storing broadcast data length, a length of the broadcast data, including performing a DMA operation with a well-known memory location of the broadcast data length memory region; and triggering, by the root node, the target node to perform a next DMA operation, including depositing, in a memory region designated for receiving injection instructions for the target node, an instruction to inject the broadcast data into the receive buffer of a subsequent target node.
摘要:
Methods, apparatus, and product for tracking network contention on links among compute nodes of an operational group in a point-to-point data communications network of a parallel computer are disclosed. In embodiments of the present invention, each compute node is connected to an adjacent compute node in the point-to-point data communications network through a link. Tracking network contention according to embodiments of the present invention includes maintaining, by a network contention module on each compute node in the operational group, a local contention counter for each compute node, each local contention counter representing network contention on links among the compute nodes originating from the compute node; and maintaining a global contention counter, the global contention counter representing network contention currently on all links among the compute nodes in the operational group.
摘要:
Methods, apparatus, and products are disclosed for providing policy-based operating system services in a hypervisor on a computing system. The computing system includes at least one compute node. The compute node includes an operating system and a hypervisor. The operating system includes a kernel. The hypervisor comprising a kernel proxy and a plurality of operating system services of a service type. Providing policy-based operating system services in a hypervisor on a computing system includes establishing, on the compute node, a kernel policy specifying one of the operating system services of the service type for use by the kernel proxy, and accessing, by the kernel proxy, the specified operating system service. The computing system may also be implemented as a distributed computing system that includes one or more operating system service nodes. One or more of the operating system services may be distributed among the operating system service nodes.
摘要:
Direct injection of a data to be transferred in a hybrid computing environment that includes a host computer and a plurality of accelerators, the host computer and the accelerators adapted to one another for data communications by a system level message passing module. Each accelerator includes a Power Processing Element (‘PPE’) and a plurality of Synergistic Processing Elements (‘SPEs’). Direct injection includes reserving, by each SPE, a slot in a shared memory region accessible by the host computer; loading, by each SPE into local memory of the SPE, a portion of data to be transferred to the host computer; executing, by each SPE in parallel, a data processing operation on the portion of the data loaded in local memory of each SPE; and writing, by each SPE, the processed data to the SPE's reserved slot in the shared memory region accessible by the host computer.
摘要:
Performing a scattery operation on a hierarchical tree network optimized for collective operations including receiving, by the scattery module installed on the node, from a nearest neighbor parent above the node a chunk of data having at least a portion of data for the node; maintaining, by the scattery module installed on the node, the portion of the data for the node; determining, by the scattery module installed on the node, whether any portions of the data are for a particular nearest neighbor child below the node or one or more other nodes below the particular nearest neighbor child; and sending, by the scattery module installed on the node, those portions of data to the nearest neighbor child if any portions of the data are for a particular nearest neighbor child below the node or one or more other nodes below the particular nearest neighbor child.
摘要:
Methods, apparatus, and products are disclosed for dispatching packets on a global combining network of a parallel computer comprising a plurality of nodes connected for data communications using the network capable of performing collective operations and point to point operations that include: receiving, by an origin system messaging module on an origin node from an origin application messaging module on the origin node, a storage identifier and an operation identifier, the storage identifier specifying storage containing an application message for transmission to a target node, and the operation identifier specifying a message passing operation; packetizing, by the origin system messaging module, the application message into network packets for transmission to the target node, each network packet specifying the operation identifier and an operation type for the message passing operation specified by the operation identifier; and transmitting, by the origin system messaging module, the network packets to the target node.
摘要:
DMA transfer completion notification includes: inserting, by an origin DMA engine on an origin node in an injection first-in-first-out (‘FIFO’) buffer, a data descriptor for an application message to be transferred to a target node on behalf of an application on the origin node; inserting, by the origin DMA engine, a completion notification descriptor in the injection FIFO buffer after the data descriptor for the message, the completion notification descriptor specifying a packet header for a completion notification packet; transferring, by the origin DMA engine to the target node, the message in dependence upon the data descriptor; sending, by the origin DMA engine, the completion notification packet to a local reception FIFO buffer using a local memory FIFO transfer operation; and notifying, by the origin DMA engine, the application that transfer of the message is complete in response to receiving the completion notification packet in the local reception FIFO buffer.