Upload
mairi
View
66
Download
0
Embed Size (px)
DESCRIPTION
IBM DS3000, DS4000, and DS5000 Embedded Features and Functions. Ryan Leonard Storage and Solutions Architect. Caching. RAID controllers use cache for two purposes Buffering write requests to media Pre-fetching read requests from media Battery backup for minimum of 72 hours - PowerPoint PPT Presentation
Citation preview
© 2009 IBM Corporation
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
IBM DS3000, DS4000, and DS5000 Embedded Features and Functions
Ryan LeonardStorage and Solutions Architect
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Caching RAID controllers use cache for two purposes
– Buffering write requests to media– Pre-fetching read requests from media
Battery backup for minimum of 72 hours DS5100, DS5300 permanent cache backup (destage)
Read request
Write request
Cache slots allocated dynamically by controller based on demand Flexible cache block sizes – 4KB, 8KB, 16KB
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Read caching Intelligent read pre-fetch algorithm
– Performs analysis of inbound read streams for sequentiality– Pre-fetch cache hits extend amount of data prefetch– Will recognize ascending, descending, and ‘sparse’ patterns
Cache Disk
Host read request
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Write caching Cache mirroring for data protection Write-back and write-through modes Demand-based and age-based flushing Full-stripe write-through
– Allows full-stripe writes to bypass the cache mirroring process and write-through to media
RAID 5, 4+P
Segment
Stripe
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
So what is a “hardware XOR” anyway? An XOR is used in RAID 5 to calculate parity
– The XOR calculation can be performed in either hardware or software– Similar operation for RAID 6 ‘q’ information
A1 XOR A2 XOR A3 = Ap But more importantly… The hardware XOR functionality is embedded in a specialized cache memory controller
– Allows DMA transfers from host and drive side to cache independently with no processor interrupts
A1
B1
C1
Dp
A2
B2
Cp
D1
A3
Bp
C2
D2
Ap
B3
C3
D3
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Configuration Flexibility Immediate Availability Format (IAF) Dynamic Array Expansion (DAE) Dynamic Volume Expansion (DVE) Dynamic RAID Migration (DRM) Dynamic Segment Sizing (DSS) HotScale DACstore
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Immediate Availability Format A given logical drive, once defined via the Storage Manager, is available
almost instantaneously for usage
Array 1, RAID 5 3+P
100MB initialization region Further initialization continues in background while host reads/writes are
accepted
LUN A
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic Array Expansion (DAE) Dynamically grow a given array / RAID set
– Host I/O continues during modification operation
RAID 5, 3+P
No maximum on RAID 0 or 10 on DS3/4/5000 (7.10 or higher) Maximum of 30 drives per RAID 5/6 array
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic Array Expansion (DAE) Dynamically grow a given array / RAID set
– Host I/O continues during modification operation
RAID 5, 4+P
No maximum on RAID 0 or 10 on DS3/4/5000 (7.10 or higher) Maximum of 30 drives per RAID 5/6 array
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic Volume Expansion (DVE) Dynamically grow a given logical drive / LUN within an array
– Host I/O continues during modification operation
Logical drives >2TB supported (w. 7.10 or higher) Available on DS3000 via CLI or Script Editor
Unused Unused Unused
C C C C
B B B B
A A A A
Unused
RAID 5, 3+P - 3 LUNs defined, A, B and C
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic Volume Expansion (DVE) Dynamically grow a given logical drive / LUN within an array
– Host I/O continues during modification operation
Logical drives >2TB supported (w. 7.10 or higher) Available on DS3000 via CLI or Script Editor
Unused Unused Unused
C C C C
B B B B
A A A A
Unused
RAID 5, 3+P - 3 LUNs defined, A, B and C
C C C CB B B B
A A A A
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic RAID Migration (DRM) Dynamically modify an array from one RAID level to another
– Host I/O continues during modification operation
Any to any modification Additional drives may be required to complete operation Available on DS3000 via CLI or Script Editor
RAID 5, 3+P
A1
B1
A2
B2
A3
Bp
Ap
B3
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic RAID Migration (DRM) Dynamically modify an array from one RAID level to another
– Host I/O continues during modification operation
Any to any modification Additional drives may be required to complete operation Available on DS3000 via CLI or Script Editor
A1
B1
A2
B2
A3
Bp
Ap
B3A1 A2 A1’ A2’
B1 B2 B1’ B2’
RAID 10, 2+2
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Dynamic Segment Sizing (DSS) Dynamically modify the segment size of a specific logical drive
– Host I/O continues during modification operation
Amount of data written to a drive before moving on to the next drive in the stripe Typically used in performance tuning Available on DS3000 via CLI or Script Editor
Drive 1 Drive 2 Drive 3 Drive 4
RAID 5, 3+P64KB 64KB 64KB 64KB
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
128KB 128KB 128KB 128KB
Dynamic Segment Sizing (DSS) Dynamically modify the segment size of a specific logical drive
– Host I/O continues during modification operation
Amount of data written to a drive before moving on to the next drive in the stripe Typically used in performance tuning Available on DS3000 via CLI or Script Editor
Drive 1 Drive 2 Drive 3 Drive 4
RAID 5, 3+P
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
HotScale Addition of physical storage capacity
– Host I/O can continue during drive / enclosure addition
On-demand scalability
DS3400
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
HotScale Addition of physical storage capacity
– Host I/O can continue during drive / enclosure addition
On-demand scalability
DS3400
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
DACstore 512MB reserve for drive metadata
– Array can be ‘exported’ and/or ‘imported’
Data intact relocation
Old Controllers
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
DACstore 512MB reserve for drive metadata
– Array can be ‘exported’ and/or ‘imported’
Data intact relocation
Old Controllers
New Controllers
Statements of IBM future plans and directions are provided for information purposes only. Plans and direction are subject to change without notice.
System Storage July 2009
Reliability, Availability, Serviceability (RAS) MediaScan
– Performs scan of physical media for unreadable blocks– All instances are logged
Advanced Rebuild– Complete a drive rebuild even after encountering unreadable sectors
Enhanced Disk Drive Predictive Fault Analysis – Monitors and logs recoverable or medium errors– May fail drives preemptively if thresholds are surpassed
Concurrent controller firmware updates Event logging and reporting
– Critical alerts via e-mail and/or SNMP