Testing and reproduction of concurrency issues

• US 10,579,501 B2
• Filed: 04/04/2018
• Issued: 03/03/2020
• Est. Priority Date: 04/04/2018
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Joglekar, Amit P., Mohandas, Praveen
• Primary Examiner(s): Khatri, Anil
• Application Number:
  US15/944,831
• Publication Number:
  US 20190310930A1
• Time in Patent Office: 699 Days
• Field of Search: 717124-131, 717140-143
• CPC Class Codes: G06F 11/3632 of specific synchronisation aspects
• CPC Class Codes: G06F 11/3636 by tracing the execution of the program
• CPC Class Codes: G06F 11/3644 by instrumenting at runtime
• CPC Class Codes: G06F 11/3664 Environments for testing or debugging software
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms
• CPC Class Codes: G06F 9/547 Remote procedure calls [RPC]; Web services

Abstract

A method and system for testing a server code in a server concurrently handling multiple client requests create a job-specific breakpoint in the server code using a library application programming interface (API) that allows the job-specific breakpoint in the server code being enabled or disabled based on a job identifier. The library API controls the job-specific breakpoint in the server code via a plurality of readymade functions that execute, in a desired sequence, various synchronous and asynchronous program paths associated with the multiple client requests. By using the library API, the method and system are capable of establishing a new server connection with the server and retrieving the job identifier from the server associated with the established new server connection, pausing execution of a client job based on enabling the job-specific breakpoint, and resuming execution of the client job based on disabling the job-specific breakpoint.

Claims

1. A method for testing a server code in a server concurrently handling multiple client requests, the method comprising:

creating a job-specific breakpoint in the server code using a library application programming interface, wherein the job-specific breakpoint in the server code is enabled or disabled based on a job identifier dynamically retrieved during execution of the server code using the library application programming interface, the library application programming interface controls the job-specific breakpoint in the server code, the library application programming interface comprises,

a plurality of readymade functions that execute, in a desired sequence, various synchronous and asynchronous program paths associated with the multiple client requests and are capable of establishing a new server connection with the server and retrieving the job identifier from the server associated with the established new server connection;

based on the job identifier, pausing an execution of a client job by based on enabling the job-specific breakpoint in the server code using the library application programming interface;

based on the job identifier, resuming the execution of the client job by based on disabling the job-specific breakpoint in the server code using the library application programming interface;

debugging and reproducing one or more concurrency issues in the server code based on

the pausing and resuming of the execution of the client job; and

writing, using the library application programming interface, readable and repeatable

reproduction scripts and test cases containing interleaved executions of parallel client requests through various breakpoints.

2. The method of claim 1, further comprising:

an application programming interface to create a new thread of execution for every client request executed in the client job using syntax of the programming language used for implementing the library application programming interface.

3. The method of claim 1, wherein the library application programming interface retains information about relationships between client jobs, job identifiers, threads, and breakpoints including node specific breakpoints.

4. The method of claim 1, wherein the library application programming interface allows queuing of client requests.

5. The method of claim 1, wherein the server code is tested based on one or more of the following interactions:

interaction between synchronous and asynchronous execution of client requests submitted concurrently from two or more different client jobs;

interaction between nodes of the server; and

interaction between asynchronous execution of a previous client request and synchronous and asynchronous execution of a subsequent client request in same client job for a given client.

6. The method of claim 5, wherein the one or more interactions are a result of a state change including failure of a node in a cluster or any state change in a specialized state-machine used by server components.

7. The method of claim 1, wherein the job-specific breakpoint is located in a synchronous execution path or an asynchronous execution path in the server code.

8. The method of claim 1, further comprising:

performing one or more of the following error checks using the library application programming interface;

determining whether a client job has been created;

determining whether the client job is currently executing another client request;

determining whether execution of the another client request is currently paused at a job-specific breakpoint;

determining whether execution of the client job is currently paused at a specified asynchronous breakpoint;

determining whether there is no future breakpoint specified for the client job; and

determining whether a future breakpoint has been specified for the client job.

9. The method of claim 1, further comprising:

creating the job-specific breakpoint in the server code for a node of the server using the library application programming interface; and

pausing execution of the client job based on enabling the job-specific breakpoint in the server code for the node of the server using the library application programming interface.

10. The method of claim 1, further comprising:

deleting the job-specific breakpoint in the server code for a node of the server using the library application programming interface; and

resuming execution of the client job based on disabling, the job-specific breakpoint in the server code for the node of the server using the library application programming interface.

11. A computer system for testing a server code in a server concurrently handling multiple client requests, the computer system comprising:

one or more processors, one or more computer-readable memories, one or more computer-readable tangible storage devices, and program instructions stored on at least one of the one or more storage devices for execution by at least one of the one or more processors via at least one of the one or more memories, wherein the computer system is capable of performing a method comprising;

creating a job-specific breakpoint in the server code using a library application programming interface,

wherein the job-specific breakpoint in the server code is enabled or disabled based on a job identifier dynamically retrieved during execution of the server code using the library application programming interface, the library application programming interface controls the job-specific breakpoint in the server code, the library application programming interface comprises,

a plurality of readymade functions that execute, in a desired sequence, various synchronous and asynchronous program paths associated with the multiple client requests and are capable of establishing a new server connection with the server and retrieving the job identifier from the server associated with the established new server connection;

based on the job identifier, pausing an execution of a client job by based on enabling the job-specific breakpoint in the server code using the library application programming interface;

based on the job identifier, resuming the execution of the client job by based on disabling the job-specific breakpoint in the server code using the library application programming interface;

debugging and reproducing one or more concurrency issues in the server code based on

the pausing and resuming of the execution of the client job; and

writing, using the library application programming interface, readable and repeatable

reproduction scripts and test cases containing interleaved executions of parallel client requests through various breakpoints.

12. The computer system of claim 11, further comprising:

an application programming interface to create a new thread of execution for every client request executed in the client job using syntax of the programming language used for implementing the library application programming interface.

13. The computer system of claim 11, wherein the library application programming interface retains information about relationships between client jobs, job identifiers, threads, and breakpoints including node specific breakpoints.

14. The computer system of claim 11, wherein the library application programming interface allows queuing of client requests.

15. The computer system of claim 11, wherein the server code is tested based on one or more of the following interactions:

interaction between synchronous and asynchronous execution of client requests submitted concurrently from two or more different client jobs;

interaction between nodes of the server; and

interaction between asynchronous execution of a previous client request and synchronous and asynchronous execution of a subsequent client request in same client job for a given client.

16. The computer system of claim 15, wherein the one or more interactions are a result of a state change including failure of a node in a cluster or any state change in a specialized state-machine used by server components.

17. The computer system of claim 11, wherein the job-specific breakpoint is located in a synchronous execution path or an asynchronous execution path in the server code.

18. The computer system of claim 11, further comprising:

performing one or more of the following error checks using the library application programming interface;

determining whether a client job has been created;

determining whether the client job is currently executing another client request;

determining whether execution of the another client request is currently paused at a breakpoint;

determining whether execution of the client job is currently paused at a specified asynchronous breakpoint;

determining whether there is no future breakpoint specified for the client job; and

determining whether a future breakpoint has been specified for the client job.