SAS Controller Virtual Lanes for Data Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing storage architectures using Serially Attached Small Computer System Interface (SAS) expanders face limitations due to hardware constraints, leading to reduced availability of memory drives and increased costs, as well as latency and congestion issues when cache space is filled, and a single memory drive can only connect to a maximum of two expander lanes.
Innovation Solution
A method and system that fragment I/O operations into blocks, map logical memory addresses to physical addresses, and estimate a reduced number of virtual lanes required for data transmission using analysis techniques, eliminating the need for dedicated physical lanes and enhancing buffer strength by creating virtual lanes that can be minimized and passivated after use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If physical expander lanes are used to connect memory drives to SAS controllers, then data transmission capability is provided, but hardware costs increase and lane availability is limited due to hardware constraints
Solution Approach 1:
The patent creates virtual copies of physical expander lanes through software-based virtual lane implementations. These virtual lanes replicate the functionality of physical lanes without requiring additional hardware, allowing multiple logical connections to be established over shared physical infrastructure. This copying approach enables unlimited lane availability while eliminating the need for costly additional physical expanders and lanes.
2Quantity of substance
If cache space is filled with data blocks, then temporary storage capacity is maximized, but processor computation cycle experiences latency due to unprocessed data blocks
Solution Approach 1:
The patent implements dynamic cache management where virtual lanes actively monitor and manage data block flow between cache memory and processing units. When cache fill levels approach thresholds that would cause processor latency, the system dynamically adjusts data transmission rates and prioritizes processing of high-priority blocks. This dynamic control prevents cache overflow conditions that would otherwise stall the processor, maintaining optimal throughput while maximizing usable cache capacity.
3Ease of manufacture
If a single memory drive connects to maximum two expander lanes, then hardware connection constraints are satisfied, but drive availability and lane utilization are highly limited
Solution Approach 1:
The patent makes expander lanes universal by implementing virtual lane technology that allows any physical lane to serve multiple memory drives through time-multiplexed connections. Instead of dedicating specific physical lanes to specific drives (which limits each drive to two connections), the system allows any lane to dynamically connect to any drive as needed. This multi-functional approach maintains hardware simplicity while dramatically increasing drive availability and lane utilization efficiency.
4Reliability
If additional SAS expanders are deployed to ensure redundancy, then system reliability is improved, but costs in terms of hardware resources increase
Solution Approach 1:
The patent replaces the mechanical hardware-based redundancy approach with a software-based virtual lane system. Instead of deploying additional physical SAS expanders to create redundant paths, the system uses virtual lane technology to establish multiple logical communication paths over shared physical infrastructure. This substitution eliminates the need for costly additional hardware while maintaining equivalent or superior redundancy levels through software-controlled failover and load balancing mechanisms.
Data Source
AI summary
Disclosed herein is a method and Serially Attached SCSI (SAS) controller for transmitting data using SCSI. In an embodiment, a plurality of I/O operations received from a storage unit are fragmented into a plurality of blocks. Further, each of the plurality of blocks are mapped with corresponding memory drives. Thereafter, a reduced number of virtual lanes required for transmitting the plurality of blocks to the corresponding memory drives is estimated. Finally, the reduced number of virtual lanes are created for transmitting the plurality of blocks to the corresponding memory drives. In an embodiment, the present disclosure uses virtual lanes for transmitting data, thereby eliminating requirement of dedicated, physical lanes for transmitting the data. Consequently, according to embodiments of present disclosure, the SAS controller may be configured to simultaneously activate multiple virtual lanes for completing the data transmission, thereby resulting in faster and reliable data transmission.