US 12,248,801 B2
Update of virtual machines using clones
Kashish Bhatia, Bangalore (IN)
Assigned to VMware LLC, Palo Alto, CA (US)
Filed by VMWARE, INC., Palo Alto, CA (US)
Filed on Feb. 8, 2022, as Appl. No. 17/666,580.
Claims priority of application No. 202141057069 (IN), filed on Dec. 8, 2021.
Prior Publication US 2023/0176889 A1, Jun. 8, 2023
Int. Cl. G06F 9/455 (2018.01); G06F 8/65 (2018.01)
CPC G06F 9/45558 (2013.01) [G06F 8/65 (2013.01); G06F 2009/45562 (2013.01); G06F 2009/45579 (2013.01); G06F 2009/45583 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of updating a virtual machine (VM), the method comprising:
initiating updating of the VM on a host in a datacenter;
creating a clone of the VM on the host, in response to initiating the update;
receiving a first write input/output (I/O) request for a first data block;
checking a first disk bitmap associated with a first delta disk for whether a first bit associated with the first data block is set, wherein the first disk bitmap includes a bit for each data block of the first delta disk indicating whether the data block has been modified, and wherein the first delta disk is associated with the clone of the VM;
based on the first bit being set, checking a scanner bitmap for whether a second bit associated with the first data block is set, wherein the scanner bitmap includes a bit for each data block of the first delta disk indicating whether the data block is currently being merged into a second disk, and wherein the second disk is associated with the VM; and
based on the second bit being set:
waiting until the first data block is merged into a second disk; and
performing the first write I/O to the first data block in the second disk after the first data block is merged into the second disk.