On-demand paging-in of pages with read-only file system

Abstract

Disclosed is a computer implemented method to resume a process at an arrival machine that is in an identical state to a frozen process on a departure machine. The arrival machine receives checkpoint data for the process from the departure machine. It creates the process. It updates a page table, wherein the page table comprises a segment, page number, and offset corresponding to a page of the process available from a remote paging device, wherein the remote paging device is remote from the arrival machine. It resumes the process and responsively generates a page fault for the page. It looks up the page in the page table, responsive to the page fault. It determines whether the page is absent in the arrival machine. It transmits a page-in request to the departure machine, responsive to a determination that the page is absent. It receives the page from the departure machine.

1 . A computer implemented method to resume a process to an arrival machine from a departure machine, the method comprising:
 receiving checkpoint data for the process from the departure machine;   creating the process based on the checkpoint data;   updating a page table, wherein the page table comprises a segment, page number, and offset corresponding to a page of the process available from a remote paging device;   resuming the process;   responsive to resuming the process, generating a page fault for the page;   responsive to the page fault, looking up the page in the page table;   determining whether the page is absent in the arrival machine;   responsive to a determination that the page is absent, transmitting a page-in request to the departure machine; and   receiving the page from the departure machine.   
     
     
         2 . The computer implemented method of  claim 1 , further comprising:
 creating a remote paging kernel process to correspond to the remote paging device of the page.