Storage Controller Virtual Disk Allocation

Solution Overview

Problem

In storage systems using thin provisioning, the sequential I/O performance is often degraded due to dispersed allocation of regions on physical disks, and the time taken to write data is increased by dynamic allocation policies based on I/O patterns, leading to performance degradation.

Innovation Solution

A storage controlling apparatus that estimates access frequency for new virtual disks based on existing virtual machines and temporarily reserves successive allocation units on physical disks when the estimated access frequency exceeds a threshold, optimizing allocation and reducing I/O performance degradation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If thin provisioning is used to efficiently utilize physical disk regions, then storage capacity utilization is improved, but sequential I/O performance degrades due to dispersed allocation of regions on physical disks

Engineering Contradiction:

Improvestorage capacity utilizationVSAvoidsequential I/O performance

Core Design Contradiction:

Quantity of substanceVSSpeed

Solution Approach 1:

The system performs preliminary allocation of successive physical disk regions to virtual disks before actual data writing occurs. By pre-allocating contiguous blocks and maintaining reservation information, the system ensures that when data needs to be written, the physical regions are already prepared and accessible, eliminating the need for dynamic allocation during I/O operations and thus maintaining sequential I/O performance while still enabling efficient thin provisioning.

Inventive Principle:

Principle #10Preliminary action

2Adaptability or versatility

If dynamic allocation policy is used to allocate disk pool regions based on I/O patterns, then storage flexibility is improved, but writing time increases and performance degrades

Engineering Contradiction:

Improvestorage flexibilityVSAvoidwriting time

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

The system performs preliminary allocation of successive physical disk regions to virtual disks before actual data writing occurs. By pre-allocating contiguous blocks and maintaining reservation information, the system ensures that when data needs to be written, the physical regions are already prepared and accessible, eliminating the need for dynamic allocation during I/O operations and thus maintaining sequential I/O performance while still enabling efficient thin provisioning.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system monitors I/O patterns and uses this feedback to manage allocation reservations. When a virtual disk is created or expanded, the system analyzes access patterns and dynamically adjusts the reservation strategy. This feedback mechanism allows the system to maintain flexibility in allocation while ensuring that frequently accessed data has pre-reserved contiguous physical space, thereby reducing writing time and improving performance.

Inventive Principle:

Principle #23Feedback

3Productivity

If thin provisioning is used to allocate disk regions dynamically, then storage efficiency is improved, but I/O performance degrades due to dispersed region allocation

Engineering Contradiction:

Improvestorage efficiencyVSAvoidI/O performance

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system performs preliminary allocation of successive physical disk regions to virtual disks before actual data writing occurs. By pre-allocating contiguous blocks and maintaining reservation information, the system ensures that when data needs to be written, the physical regions are already prepared and accessible, eliminating the need for dynamic allocation during I/O operations and thus maintaining sequential I/O performance while still enabling efficient thin provisioning.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS9983806B2Storage controlling apparatus, information processing apparatus, and computer-readable recording medium having stored therein storage controlling program

Publication Date: 2018.05.29 FUJITSU LTD

AI summary

A storage controlling apparatus includes a processor. The processor estimates, when a new virtual machine is to be produced, an access frequency to a new virtual disk to be allocated to the new virtual machine based on an access frequency to an existing virtual disk allocated to an existing virtual machine produced from master information on which the new virtual machine is based, and temporarily reserves, when the estimated access frequency exceeds a first threshold value, a plurality of successive allocation unit regions in a physical disk for the new virtual disk.