Rescheduling of virtual machine migrations with less impact on an existing migration schedule

Patent metadata

Field	Value
Publication number	US-2020257554-A1
Application number	US-202016773249-A
Country	US
Kind code	A1
Filing date	Jan 27, 2020
Priority date	Feb 8, 2019
Publication date	Aug 13, 2020
Grant date	—

Abstract

An apparatus, for an existing schedule indicating time slots during which virtual-machines are to be migrated between physical-machines, acquires change information indicating a change of first time slots during which first virtual-machines are to be migrated, and generates constraint information including a group of constraints regarding the change information and second time slots during which second virtual-machines other than the first virtual-machines are to be migrated. The apparatus generates semi-constraint information items each generated by excluding, from the constraint information, an exclusion target constraint that is selected in turn from among the group of constraints, and generates, for each semi-constraint information item, a rescheduling result by rescheduling migrations of the virtual-machines. The apparatus outputs a first rescheduling result that is one of the generated rescheduling results which reduces a difference between a scheduled migration time indicated by the first rescheduling result and scheduled migration times of the second virtual-machines.

First claim

What is claimed is:

1 . A non-transitory, computer-readable recording medium having stored therein a program for causing a computer to execute a process comprising:
for an existing schedule indicating time slots during which a plurality of virtual machines are to be migrated between a plurality of physical machines, acquiring change information indicating a change of first time slots during which first virtual machines are to be migrated; generating constraint information including a group of constraints regarding the change information and second time slots during which second virtual machines other than the first virtual machines are to be migrated; generating a plurality of semi-constraint information items each generated by excluding, from the constraint information, an exclusion target constraint that is selected in turn from among the group of constraints; generating, for each of the plurality of semi-constraint information items, a rescheduling result by rescheduling migrations of the plurality of virtual machines; and outputting a first rescheduling result that is one of the generated rescheduling results which reduces a difference between a scheduled migration time indicated by the first rescheduling result and scheduled migration times of the second virtual machines.

2 . The non-transitory, computer-readable recording medium of claim 1 , wherein, in the generating the plurality of semi-constraint information items, a constraint included in a minimal unsatisfiable core extracted from the group of constraints is selected as the exclusion target constraint.

3 . The non-transitory, computer-readable recording medium of claim 2 , wherein some of constraints included in the minimal unsatisfiable core are selected as the exclusion target constraint, based on a priority of each of the plurality of virtual machines.

4 . The non-transitory, computer-readable recording medium of claim 1 , wherein, in the outputting the first rescheduling result, the first rescheduling result which reduces a first difference between a scheduled migration time indicated by the first rescheduling result and scheduled migration times of the second virtual machines or a second difference between a scheduled migration time slot indicated by the change information and scheduled migration time slots indicated by the first rescheduling result is output.

5 . The non-transitory, computer-readable recording medium of claim 4 , wherein, in the outputting the first rescheduling result, the first rescheduling result that minimizes either one of the first difference and the second difference is output.

6 . The non-transitory, computer-readable recording medium of claim 1 , wherein the change information includes information indicating a time slot in which a migration of each of the first virtual machines is allowed or a time slot in which a migration of each of the first virtual machines is to be avoided.

7 . The non-transitory, computer-readable recording medium of claim 1 , wherein the constraint information includes a constraint related to a maintenance period during which a maintenance is to be performed on each of the plurality of physical machines, configurations of the plurality of physical machines and the plurality of virtual machines, and a turnaround time for a migration of each of the plurality of virtual machines between the plurality of physical machines.

8 . The non-transitory, computer-readable recording medium of claim 7 , wherein, in the generating the first rescheduling result, a time period for performing a maintenance on each of the plurality of physical machines is determined, from among the maintenance periods, based on the plurality of semi-constraint information items and a turnaround time for a maintenance of each of the plurality of physical machines.

9 . An apparatus comprising:
a memory; and a processor coupled to the memory and configured to:
for an existing schedule indicating time slots during which a plurality of virtual machines are to be migrated between a plurality of physical machines, acquire change information indicating a change of first time slots during which first virtual machines are to be migrated;
generate constraint information including a group of constraints regarding the change information and second time slots during which second virtual machines other than the first virtual machines are to be migrated;
generate a plurality of semi-constraint information items each generated by excluding, from the constraint information, an exclusion target constraint that is selected in turn from among the group of constraints;
generate, for each of the plurality of semi-constraint information items, a rescheduling result by rescheduling migrations of the plurality of virtual machines; and
output a first rescheduling result that is one of the generated rescheduling results which reduces a difference between a scheduled migration time indicated by the first rescheduling result and scheduled migration times of the second virtual machines.

10 . A method performed by a computer, the method comprising:
for an existing schedule indicating time slots during which a plurality of virtual machines are to be migrated between a plurality of physical machines, acquiring change information indicating a change of first time slots during which first virtual machines are to be migrated; generating constraint information including a group of constraints regarding the change information and second time slots during which second virtual machines other than the first virtual machines are to be migrated; generating a plurality of semi-constraint information items each generated by excluding, from the constraint information, an exclusion target constraint that is selected in turn from among the group of constraints; generating, for each of the plurality of semi-constraint information items, a rescheduling result by rescheduling migrations of the plurality of virtual machines; and outputting a first rescheduling result that is one of the generated rescheduling results which reduces a difference between a scheduled migration time indicated by the first rescheduling result and scheduled migration times of the second virtual machines.

Assignees

• Fujitsu Ltd

Inventors

• Okuno Shingo
• Watanabe Yukihiro
• Iikura Fumi

Classifications

• G06F2009/4557

  Distribution of virtual machine instances; Migration and load balancing · CPC title

• G06F9/4856 Primary

  resumption being on a different machine, e.g. task migration, virtual machine migration (G06F9/5088 takes precedence) · CPC title

• G06F2209/5013

  Request control · CPC title

• G06F9/5077 Primary

  Logical partitioning of resources; Management or configuration of virtualized resources (specific details on emulation or internal functioning of virtual machines G06F9/455) · CPC title

• G06F2209/485

  Resource constraint · CPC title