Checkpoint and rewind method and apparatus in serverless platform

1 . A checkpoint and rewind method in a serverless platform performed by at least one processor, the method comprising:

receiving a function execution request on the serverless platform;

storing an initial state of a sandbox by performing a checkpoint operation on the sandbox associated with the function execution request; and

after a task corresponding to the function execution request is completed, restoring a state of the sandbox to the initial state by performing a rewind operation on the sandbox,

wherein the storing of the initial state for the memory area of the sandbox includes copying a page table entry (PTE) on an original page table onto a buddy page table, and

wherein the copying of the page table entry on the original page table onto the buddy page table includes, when a first page table entry on the original page table is writable, changing the first page table entry to a non-writable one and copying the first page table entry onto the buddy page table.

2 . The method of claim 1 , wherein the storing of the initial state of the sandbox includes:

storing an initial state for a memory area of the sandbox.

3 . The method of claim 1 , wherein the copying of the page table entry on the original page table onto the buddy page table includes:

applying a copy-on-write (CoW) algorithm to the original page table and the buddy page table.

4 . The method of claim 1 , wherein the copying of the page table entry on the original page table onto the buddy page table further includes:

when the first page table entry on the original page table is changed, maintaining the first page table entry copied onto the buddy page table.

5 . The method of claim 1 , wherein the copying of the page table entry on the original page table onto the buddy page table includes:

when a read fault occurs, copying a second page table entry associated with the read fault onto the original page table and the buddy page table.

6 . The method of claim 1 , wherein the copying of the page table entry on the original page table onto the buddy page table includes:

when a write fault for a file-backed page occurs, copying a third page table entry associated with the file-backed page onto the buddy page table so as to reference an original copy.

7 . The method of claim 1 , wherein the copying of the page table entry on the original page table onto the buddy page table includes:

when a write fault for an anonymous page occurs, copying a fourth page table entry associated with the anonymous page onto the buddy page table in a writable form.

8 . The method of claim 1 , wherein the restoring of the state of the sandbox to the initial state by performing the rewind operation on the sandbox includes:

when the original page table and the buddy page table share a page frame number (PFN) of a page table entry, maintaining a page table entry of the original page table sharing the page frame number.

9 . The method of claim 1 , wherein the restoring of the state of the sandbox to the initial state by performing the rewind operation on the sandbox includes:

when the original page table and the buddy page table do not share a page frame number of a page table entry, restoring a page table entry of the original page table to a page table entry of the buddy page table.

10 . The method of claim 1 , wherein the storing of the initial state of the sandbox includes:

storing an initial state of a file system of the sandbox.

11 . The method of claim 10 , wherein the storing of the initial state of the file system of the sandbox includes:

storing an initial state of an upper file system, where a change is recorded, in the file system including the upper file system and a lower file system.

12 . The method of claim 11 , wherein the restoring of the state of the sandbox to the initial state by performing the rewind operation on the sandbox includes:

when a file corresponding to a first file in the upper file system is included in the lower file system or the initial state, changing the first file to a file of the lower file system or the initial state.

13 . A non-transitory computer-readable recording medium storing a program for executing the checkpoint and rewind method in the serverless platform described in claim 1 .

14 . A checkpoint and rewind method in a serverless platform performed by at least one processor, the method comprising:

receiving a function execution request on the serverless platform;

storing an initial state of a sandbox by performing a checkpoint operation on the sandbox associated with the function execution request; and

after a task corresponding to the function execution request is completed, restoring a state of the sandbox to the initial state by performing a rewind operation on the sandbox,

wherein the storing of the initial state of the sandbox includes storing an initial state of a file system of the sandbox,

wherein the storing of the initial state of the file system of the sandbox includes storing an initial state of an upper file system, where a change is recorded, in the file system including the upper file system and a lower file system, and

wherein the restoring of the state of the sandbox to the initial state by performing the rewind operation on the sandbox includes:

when a file corresponding to a second file in the upper file system is not included in the lower file system or the initial state, deleting the second file.

15 . A computing apparatus comprising:

a communication module;

a memory; and

at least one processor connected to the memory and configured to execute at least one computer-readable program included in the memory;

wherein the at least one program includes instructions for:

receiving a function execution request on a serverless platform;

storing an initial state of a sandbox by performing a checkpoint operation on the sandbox associated with the function execution request; and

after a task corresponding to the function execution request is completed, restoring a state of the sandbox to the initial state by performing a rewind operation on the sandbox,

wherein the storing of the initial state for the memory area of the sandbox includes copying a page table entry (PTE) on an original page table onto a buddy page table, and

wherein the copying of the page table entry on the original page table onto the buddy page table further includes, when the first page table entry on the original page table is changed, maintaining the first page table entry copied onto the buddy page table.