Table of contents
SmartTier intelligent grading technology
Three stages to realize SmartTier data migration
SmartQoS intelligent service quality control
SmartTier intelligent grading technology
Basic overview
Automatically dynamically match different active data and storage media with different characteristics to improve performance.
NL-SAS: A combination of SAS disk interface and SATA disk body
working principle
Initial data is stored in the capacity tier by default (can be changed to performance tier and high-performance tier)
Three stages to realize Smart Thier data migration
Three Phases of Data Migration
I/O monitoring: count the activity of different data blocks through the I/O module
Data arrangement analysis: the data arrangement module ranks the activity of different data blocks
Data Migration: The data migration module implements migration according to ranking results and data migration strategies
Data migration strategy: automatic migration, migration to high-performance layer, migration to low-performance layer, no migration
Prioritize allocation from the high-performance layer: first allocate to SSD > SAS > NL-SASPrioritize allocation from the performance tier: SAS > NL-SAS > SSDPrioritize allocation from the capacity tier: NL-SAS > SAS > SSDData migration time: It can be migrated on a regular basis (usually opened during peak hours), or it can be migrated manually
Data Migration Speed: Low, Medium, High
Precautions
1. The minimum size of data migration is: Extent 4MB
(When it is necessary to migrate 16KB of hotspot data, it is still necessary to migrate 4MB of data - only 16KB of which is hotspot data, there will be errors)
2. Smart Tier is used according to the business situation. Some businesses may not only not be tuned after use, but also cause performance degradation
3. Smart Tier dynamic data migration requires additional space for data exchange (storage needs to reserve a part of idle time)
Application Scenario
Generally used in mixed array scenarios (both SSD and HDD)
Can make full use of the storage space of the SSD disk and improve the data reading rate
SmartQoS intelligent service quality control
basic concept
Dynamically allocate storage system resources to meet certain application-specific performance goals
When deploying multiple applications on the same storage device, users can maximize the benefits of integration by properly configuring SmartQoS features
Two Key Technologies
I/O priority scheduling
The user needs to specify its priority when creating a LUN or file system (if the user does not specify it, the lowest priority will be used by default)
I/O traffic management
Implemented based on token distribution and control (the more tokens, the better)
According to the target IOPS/bandwidth limit, convert IOPS/bandwidth into tokens through the upper control limit/lower protection limit control strategy (the larger the token, the more tokens)
When the control strategy is the lower limit of protection, or more delay options (the lower the delay, the more tokens)
Application Scenario
In the case of tight resources, it is necessary to prioritize the business operation of high-level users and ensure the service quality requirements