Recording activity of software threads in a concurrent software environment

Patent metadata

Field	Value
Publication number	US-9448895-B2
Application number	US-201214110733-A
Country	US
Kind code	B2
Filing date	Apr 16, 2012
Priority date	Apr 21, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

A technique for failure monitoring and recovery of a first application executing on a first virtual machine includes storing machine state information during execution of the first virtual machine at predetermined checkpoints. An error message that includes an application error state at a failure point of the first application is received, by a hypervisor, from the first application. The first virtual machine is stopped in response to the error message. The hypervisor creates a second virtual machine and a second application from the stored machine state information that are copies of the first virtual machine and the first application. The second virtual machine and the second application are configured to execute from a checkpoint preceding the failure point. In response to receipt of a failure interrupt by the second application, one or more recovery processes are initiated in an attempt to avert the failure point.

First claim

What is claimed is:

1. A data processing system, comprising:
one or more storage devices; and
at least one processor coupled to the one or more storage devices, wherein the processor is configured to:
execute a first application on a first virtual machine;
store machine state information during execution of the first virtual machine at predetermined checkpoints;
receive an error message that includes an application error state at a failure point of the first application;
stop the first virtual machine in response to the error message;
create a copy of the first virtual machine and the first application from the stored machine state information, wherein the virtual machine copy corresponds to a second virtual machine and the application copy corresponds to a second application, and wherein the second virtual machine and the second application are configured to execute from a checkpoint preceding the failure point;
send a failure interrupt to the second application before the failure point is reached; and
initiate, in response to receipt of the failure interrupt by the second application, one or more recovery processes in an attempt to avert the failure point during execution of the second application.

2. The data processing system of claim 1 , wherein the recovery processes include one or more of cancelling one or more transactions, cancelling one or more threads, flushing one or more caches, discarding one or more data structures, and selecting a safe operating mode.

3. The data processing system of claim 1 , wherein, in response to a failure of the second application coinciding with that of the first application, subsequent recovery processes for the failure are adapted from the one or more recovery processes to increase a probability of avoiding the failure point.

4. The data processing system of claim 3 , wherein the adapted recovery processes include a recovery process with increased impact.

5. The data processing system of claim 3 , wherein the adapted recovery processes include a new recovery process and a new failure causes recovery processes to be selected based on a type of the new failure.

6. The data processing system of claim 1 , wherein the state information includes all virtual machine registers and memory for the first virtual machine.

7. A computer program product, comprising:
a non-transitory computer-readable storage memory; and
code stored on the computer-readable storage memory, wherein the code, when executed by a data processing system, causes the data processing system to:
execute a first application on a first virtual machine;
store machine state information during execution of the first virtual machine at predetermined checkpoints;

receive an error message that includes an application error state at a failure point of the first application;
stop the first virtual machine in response to the error message;
create a copy of the first virtual machine and the first application from the stored machine state information, wherein the virtual machine copy corresponds to a second virtual machine and the application copy corresponds to a second application, and wherein the second virtual machine and the second application are configured to execute from a checkpoint preceding the failure point;
send a failure interrupt to the second application before the failure point is reached; and
initiate, in response to receipt of the failure interrupt by the second application, one or more recovery processes in an attempt to avert the failure point during execution of the second application.

8. The computer program product of claim 7 , wherein the recovery processes include one or more of cancelling one or more transactions, cancelling one or more threads, flushing one or more caches, discarding one or more data structures, and selecting a safe operating mode.

9. The computer program product of claim 7 , wherein, in response to a failure of the second application coinciding with that of the first application, subsequent recovery processes for the failure are adapted from the one or more recovery processes to increase a probability of avoiding the failure point.

10. The computer program product of claim 9 , wherein the adapted recovery processes include a new recovery process and a new failure causes recovery processes to be selected based on a type of the new failure.

11. The computer program product of claim 7 , wherein the state information includes all virtual machine registers and memory for the first virtual machine.

Assignees

• North Geraint
• IBM

Inventors

• North Geraint

Classifications

• G06F11/1438 Primary

  Restarting or rejuvenating · CPC title

• G06F11/1484

  involving virtual machines · CPC title

• G06F11/20

  using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements · CPC title

• G06F2009/45591

  Monitoring or debugging support · CPC title

• G06F2201/84

  Using snapshots, i.e. a logical point-in-time copy of the data · CPC title