International Business Machines Corporation

Victor Company of Japan, Limited

Ntt Data Communications Systems Corporation

Hiroshi Horii

Michihiro Horie

Kazunori Ogata

Tamiya Onodera

Kiyokuni Kawachiya

Mikio Takeuchi

Hideki Tai

Miki M Enoki

Tatsuhiro Chiba

Hitomi Chiba

Hiroshi Inoue

Kohichi Kamijoh

Gaku Yamamoto

Hironori Takeuchi

Hisashi Miyashita

Shohei Ohsawa

Toshihiro Takahashi

Jun Doi

Takuya Mishina

Akihiko Tozawa

Yohsuke Ozawa

Takayuki Osogami

Akira Koseki

Taiga Nakamura

Toru Nagano

Rudy Raymond Harry Putra

Kazutoshi Hirohashi

Yoshiki Iwasaki

Ryo Kawahara

Naomichi Nishimoto

Takeshi Yoshimura

Shunichi Shichijo

Ikko Hamamura

Christopher James Wood

Yoshiaki Yunoki

Takaaki Takeda

Rina Nakazawa

Hideo Koike

Takeshi Nomoto

Keishi Ushijima

Akio Yoshikawa

Michio Kikuta

Akio Oka

Rina Inoue

Susumu Kakuta

Susumu Katayama

Tetsuo Fukasawa

Muhammad Anis Uddin Nasir

Techniques for circuit serialization for parameterized-circuit simulation are described. In one example, a system is provided that comprises a processor that executes computer executable components stored in memory. The computer executable components comprise a determination component that determines a first path of computational nodes and a second path of computational nodes of a parameter tree comprising a plurality of computational nodes, wherein the first path of computational nodes and the second path of computational nodes share one or more computational nodes at the beginning of the first path of computational nodes and the second path of computational nodes. The computer executable components further comprise a serialization component that creates a serialized path of computational nodes from the first path of computational nodes and the second path of computational nodes.

Circuit serialization for parameterized circuit simulation

Systems, computer-implemented methods, and computer program products to facilitate sampling-optimization for gate-level simulations are provided. According to an embodiment, a system can comprise a processor that executes computer executable components stored in memory. The computer executable components comprise a cache component that caches a state of a set of qubits within a quantum gate-level simulation after the set of qubits are reset. According to another embodiment the computer executable components further comprise an avoidance component that prevents duplicated simulation of quantum gates in the quantum gate-level simulation by using the cached state of the set of qubits to represent a quantum state produced by a previously simulated quantum gate.

Enablement of sampling-optimization for gate-level simulation

A computer-implemented method is provided for managing Garbage Collection (GC) safepoints. The method includes determining whether a GC safepoint for a target native method can be removed by checking a heap occupancy ratio prior to executing the target native method. The method further includes removing the GC safepoint responsive to the heap occupancy ratio prior to executing the target native method being less than a threshold occupancy amount percentage. The method also includes determining whether the GC safepoint for the target native method can be removed by checking a most recent GC pause time. The method additionally includes removing the GC safepoint responsive to the most recent GC pause time being shorter by a threshold pause time amount percentage than an execution time of the target native method.

Selective injection of GC safepoints for JNI invocations

A method, system and computer program product are presented for reducing memory consumption in depth first search (DFS)-based cycle detection processes to detect an n-length cycle on a Pregel model. The method includes generating a graph including a plurality of vertices and edges connecting the plurality of vertices, commencing a cycle from a first vertex of the plurality of vertices, setting an ID of the first vertex to a path and the first vertex as a target vertex, and iterating the following n−1 times: send the path to out-edges starting from the first vertex and transferring the path, via out-edges, n−1 times by subsequent received vertices, find one vertex before returning to the target vertex, add an ID of a found vertex to the path, and set the found vertex as the target vertex such that n=n−1, where is a number of iterations.

DFS-based cycle detection on Pregel model

Embodiments are provided to simulate a quantum circuit. A system receives a quantum circuit (or its representation), generates a graph, and adds edges for each n-qubit of fusion to be applied. Costs are estimated or calculated for various paths of gate fusion between endpoints in the graph. One or more paths are selected, for example, the lowest cost path based on a Dijkstra algorithm evaluation. A unitary matrix for each gate fusion is then generated for simulating the quantum circuit. A simulation is performed locally or remotely based on the gate fusions along the selected one or more paths, and thus, improving the memory and processor performance of the simulation.

Scheduling fusion for quantum computing simulation

Systems, computer-implemented methods, and computer program products to facilitate sampling of an operator in a quantum system are provided. According to an embodiment, a system can comprise a memory that stores computer executable components and a processor that executes the computer executable components stored in the memory. The computer executable components can comprise a cache component that caches a probability distribution and a quantum state of one or more Kraus operators in a quantum circuit. The computer executable components can further comprise a simulator component that simulates one or more shots of the quantum circuit based on the probability distribution and the quantum state of the one or more Kraus operators. The one or more shots are indicative of one or more algorithm execution instances.

Sampling of an operator in a quantum system

A computer-implemented method is provided for reducing a measure time of a measure process in a multi-shot simulation performed by a quantum computing simulation system. The method includes calculating probabilities from probability amplitudes before the measure process. The method further includes creating, for each node of the quantum computing simulation system, an index of probability by incrementally summing respective different ones of the probabilities into respective sums. The method also includes generating a random number for each of the multi-shots, the random number for sampling a probability distribution of the probabilities. The method additionally includes selecting the index of probability which is larger than the random number by comparing the random number generated for a given one of the multi-shots to the index of probability created for the given one of the multi-shots.

Probability index optimization for multi-shot simulation in quantum computing

Techniques facilitating controlled NOT gate parallelization in quantum computing simulation are provided. A system can comprise a memory that stores computer executable components and a processor that executes the computer executable components stored in the memory. The computer executable components can comprise a selector component that can select a first qubit and a second qubit. The first qubit can be a control qubit. The computer executable components can also comprise a parallelization component that can reorder the first qubit with the second qubit and a replication component that can simulate a controlled NOT gate during the reordering by the parallelization component.

Controlled NOT gate parallelization in quantum computing simulation

A computer-implemented method is presented for reducing data loading overhead of middleware to facilitate direct data loading to a database management system (DBMS). The method includes, while data loading, sending external-writes to a memory-based DBMS if corresponding internal-writes are for vertices, exporting all the external-writes to a disk-based DBMS as an export file, and sending an external-read for vertices to an in-memory DBMS if the middleware requests data. The method further includes, at the end of data loading, generating files for raw data of the disk-based DBMS from the export file and sending the generated raw files to the disk-based DBMS.

Direct data loading of middleware-generated records

Verified snapshots are generated by obtaining, from one of a plurality of first nodes, a difference between a common data at a first time point and the common data at a second time point that is different from the first time point, generating a first snapshot of the common data at the first time point based on the difference, obtaining a hash of the common data at the first time point from one of the plurality of first nodes, and verifying the first snapshot at the first time point with the hash of the common data at the first time point.

Management of snapshot in blockchain

Systems and methods for processing hierarchical tasks in a garbage collection mechanism are provided. The method includes determining chunks in a task queue. Each chunk is a group of child tasks created after processing one task. The method includes popping, by an owner thread, tasks from a top side of the task queue pointed at by a chunk in a first in first out (FIFO) pop. The method also includes stealing, by a thief thread, tasks from a chunk in an opposite side of the task queue.

Garbage collection work stealing mechanism

A computer-implemented method for increasing record availability on a distributed database system implementing multiple partitioning strategies includes identifying first processing devices of a distributed database system for storing one or more first records in accordance with multiple partitioning strategies, determining that at least two of the first processing devices are identified for storing a given one of the one or more first records, and selecting one or more new processing devices of the distributed database system for storing the given first record to achieve sufficiently high availability of the given record within the distributed database system.

Record replication for multi-column partitioning on distributed database systems

A computer-implemented method is provided for compilation rescheduling from among four compilation levels comprising level 1, level 2, level 3, and level 4 on a parallel distributed computing framework running processes for a plurality of jobs of a virtual machine. The method bypasses a program analysis overhead that includes measuring a compiled method execution time by identifying completed compilation levels of a Just In Time compilation. The method finds a repetition of a same process in the processes for the plurality of jobs of the virtual machine from profiles by comparing main class names, virtual machine parameters, and Jar file types therein. The method applies a compilation scheduling for the same process a next time the same process runs based on a result of the checking the transition, by (i) compiling at the level 1 at least some methods for the same process responsive to the virtual machine finishing without compiling the at least some methods for the same process at the level 4 after compiling the at least some of the methods at a level in between the level 1 and the level 4, and (ii) compiling at the level 4 at least a subset of the methods earlier than an original scheduled time responsive to at least the subset of the methods compiled at the level 4 being infrequently invoked below a threshold amount.

Rescheduling JIT compilation based on jobs of parallel distributed computing framework

Techniques for simulating a quantum circuit based on fusion of at least a portion of a measure gate is provided. Data representing a quantum circuit comprising a quantum gate and a measure gate is received. The measure gate in the quantum circuit is divided into one or more virtual gates and at least one of the one or more virtual gates is fused with the quantum gate. The gate fusion combines the operations of the fused gates and cache blocking to more efficiently simulate the quantum circuit. In one embodiment, the simulation of the quantum circuit is executed locally on a computing device. Alternatively, the simulation of the quantum circuit is performed remotely over a network via an application program interface ('API') and results of the simulation are reported via the API.

Gate fusion for measure in quantum computing simulation

A distributed system is provided that includes member nodes and a leader node. Each member node stores a database and updates the database by performing common ones of a plurality of transactions. The leader node generates a batch, to be executed by each member node, which includes two or more transactions lacking an access conflict from among the plurality of transactions. The leader node includes: a section that generates an access set as a set of database entries to be accessed by each transaction to be executed; a section that generates the batch, based on the access set of each transaction to be executed; and a leader-side section that performs a consensus process for the batch among the leader and member nodes. Each member node includes the database; a member-side section that performs a consensus process for the batch; and a section that performs parallel execution of batch transactions.

Distributed system, computer program product and method

Growing community of inventors

Tokyo, Japan

Hiroshi Horii