Multi-threaded virtual machine processing on a web page

• US 8,826,276 B1
• Filed: 09/26/2011
• Issued: 09/02/2014
• Est. Priority Date: 06/21/2011
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Menon, Vijay, Li, Peng
• Primary Examiner(s): An, Meng
• Assistant Examiner(s): LEE, TAMMY EUNHYE
• Application Number:
  US13/245,276
• Time in Patent Office: 1,072 Days
• Field of Search: None
• US Class Current: 718/1
• CPC Class Codes: G06F 9/4843 by program, e.g. task dispatcher, supervisor, operating system

Abstract

A system, method and a computer-readable medium for processing resources on a multithreaded browser. The browser includes a main thread and receives a resource. The browser initializes the main thread, the main thread includes an event loop and initializes a plurality of virtual machines, one virtual machine for each code segment within the resource. Each virtual machine includes a UI thread and is configured to share the main thread within the browser with the UI thread. Each UI thread is further configured to execute an event scheduled on the event loop on the virtual machine.

Claims

1. A computer-implemented method for processing resources on a multi-threaded browser, comprising:

using a main thread included in the multi-threaded browser to initialize a plurality of virtual machines for processing a resource having a plurality of code segments wherein each virtual machine processes a respective code segment of the resource;

scheduling, using the main thread, a plurality of events for processing the plurality of code segments of the resource in parallel, wherein the scheduling further comprises for each event;

cooperatively mapping the main thread within the multi-threaded browser to a UI thread executing within a respective virtual machine;

activating a respective event handler within the UI thread of each respective virtual machine to assign the event in the cooperatively mapped main thread included in the browser to the UI thread included in the respective virtual machine; and

executing the event using the respective virtual machine.

2. The computer-implemented method of claim 1, wherein the main thread includes an event loop for scheduling the plurality of events.

3. The computer-implemented method of claim 2, further comprising:

receiving a stop-the-world event in the main thread, the stop-the-world event issued by a virtual machine;

asynchronously scheduling the stop-the-world event on the event loop of the main thread;

retrieving the stop-the-world event from the event loop using the main thread;

mapping the main thread to the virtual machine that issued the stop-the-world event; and

processing the stop-the-world event using the virtual machine.

4. The computer-implemented method of claim 3, wherein the stop-the-world event includes a garbage collection.

5. The computer-implemented method of claim 1, wherein the cooperatively mapping is event driven.

6. The computer-implemented method of claim 1, wherein the executing further comprises:

assigning the event in the UI thread to one or more background threads within the respective virtual machine for processing.

7. The computer-implemented method for context switching on a multi-threaded browser, comprising:

processing within a first virtual machine having an event handler associated with a first UI thread on the first virtual machine a first event of a plurality of events for processing a resource having a plurality of code segments, the first virtual machine executing on the multi-threaded browser;

receiving a call to access an event handler associated with a second UI thread on a second virtual machine, from the event handler associated with the first UI thread on the first virtual machine, the second virtual machine executing on the multi-threaded browser in parallel with the first virtual machine;

mapping a main thread of the multi-threaded browser to the event handler associated with the first UI thread on the first virtual machine to retrieve a record including a memory state of the first virtual machine prior to a context switch;

storing the record within the main thread of the multi-threaded browser;

context switching the main thread from the first virtual machine to the second virtual machine;

accessing a second event from an event loop within the main thread;

executing the second event using the event handler associated with the second UI thread on the second virtual machine; and

restoring the processing of the first event to the first virtual machine, once the execution of the second event on the second virtual machine is complete, wherein the restoring execution to the first virtual machine causes the main thread to access the record and restore a memory state of the first virtual machine to the memory state prior to the context switch.

8. The method of claim 7, wherein the context-switching is event driven.

9. The method of claim 7, wherein the main thread includes a virtual memory invocation stack, and wherein the restoring further comprises accessing the record of the first virtual machine within the virtual memory invocation stack of the main thread.

10. A system, comprising:

a processor coupled with a memory; and

a multi-threaded browser stored in the memory and configured to execute a main thread on the processor to process a resource having a plurality of code segments; and

wherein the main thread is configured to;

use the main thread included in the multi-threaded browser to initialize a plurality of virtual machines for processing respective code segments of the resource; and

schedule, using the main thread, a plurality of events for processing the plurality of code segments of the resource in parallel, wherein the main thread is configured to schedule each event to;

cooperatively map the main thread within the browser to a UI thread executing within a respective virtual machine;

activate an event handler within the UI thread of each respective virtual machine to assign the respective event in the cooperatively mapped main thread included in the browser to the UI thread included in the respective virtual machine; and

execute the respective event using the respective virtual machine.

11. The system of claim 10, wherein the main thread includes an event loop for scheduling the plurality of events.

12. The system of claim 10, wherein the main thread is further configured to:

receive a stop-the-world event in the main thread, the stop-the-world event issued by a virtual machine;

asynchronously schedule the stop-the-world event on the event loop of the main thread;

retrieve the stop-the-world event from an event loop using the main thread;

map the main thread to the virtual machine that issued the stop-the-world event; and

process the stop-the-world event in the virtual machine.

13. The system of claim 12, wherein the stop-the-world event includes a garbage collection.

14. The system of claim 10, wherein the main thread is configured to schedule each event to cooperatively map the main thread within the browser to a UI thread within a respective virtual machine such that the cooperative mapping is event driven.

15. A system, comprising:

a processor coupled with a memory;

a multi-threaded browser stored in the memory and executing on the processor a main thread;

a first virtual machine executing on the multi-threaded browser and configured to;

process within a first virtual machine having an event handler associated with a first UI thread on the first virtual machine a first event of a plurality of the events for processing a resource having a plurality of code segments;

receive a call to access an event handler associated with a second UI thread on a second virtual machine, from the event handler associated with the first UI thread on the first virtual machine, the second virtual machine executing on the multi-threaded browser in parallel with the first virtual machine;

the main thread configured to;

map to the event handler of the first virtual machine to retrieve a record including the state of the first virtual machine;

store the record within the main thread of the multi-threaded browser;

access a second event from the event loop within the main thread;

context switch from the first virtual machine to the second virtual machine wherein the second virtual machine executes the second event using an event handler associated with the second UI thread on the second virtual machine; and

restore the processing of the first event to the first virtual machine, once the execution of the second event on the second virtual machine is complete, wherein the restoring execution to the first virtual machine causes the main thread to access the record and restore a memory state of the first virtual machine to the memory state prior to the context switch.

17. The system of claim 15, wherein the context-switching is event driven.

16. The system of 15, wherein the main thread includes a virtual memory invocation stack, and wherein the main thread is further configured to access the virtual memory invocation stack for the record of the first virtual machine to restore the execution.