ssd and enteprise storage
DESCRIPTION
SSD general intro and its application in enterprise storage environmentTRANSCRIPT
SSD and itsApplication in Enterprise
Storage
Frank Zhao
What’s SSD ? SSD (Solid State Drive): semiconductor-based block storage
device that appears to the host devices like a disk drive -IDC,2007
Other terms:
EFD (Enterprise Flash Drive, EMC) SCM (Storage Class Mem, IBM)
Types: DRAM + battery Flash based
NOR flash NAND flash
Why SSD ?Disk drive becomes the performance bottleneck!
Multiple core (Intel Nehalem)
DDR3-1333: 10GB/sQFI: 25.6GB/sPCIe*16: 8GB/sFC disk: 150MB/s!
Flash instead of spindle/platter NAND flash: high density, long endurance
Behaves like disk: Sector/page-based and well-suited for sequential data (pictures, audio,
and files) Bad block
Unlike disk : Wear out the cell
Two NAND types: SLC (single-level cell)
3X fast , 10X long endurance to MLC
MLC (multi-level cell) 2~3X more capacity than SLC
for enterprise
for consumer
NAND Flash internal
Data is grouped into block/page Page: 2K/4KB (plus spare area: 64B/128B) Block: 64/128 pages, up to 512KB
Special ops: Erase: set all bits within block to “1”
The smallest erasable entity is a block Program: change bit from “1”to “0”
SSD product Interface:
FC/SATA/SAS/ PCIe USB …
Property Performance Endurance Capacity Cost
SSD - PerformanceModel HDD
Intel X25-E
STEC ZEUSIOPS
Media TypeHDD15K
rpmSLC SLC
Capacity (GB) 600 64 73
User Space Rate -59.6/80
= 74.5%
73/128
=57%Cache (MB) 16 16 512
Access Time (ms) 3.4R 0.075,
W 0.0850.02~0.12
Sustained Read (MB/s)
147 250 220
Sustained Write (MB/s)
134 170 115
Random Read (IOPS)
250 35,000 46,000
Random Write (IOPS)
250 3,300 16,000
260XCache rate
30X ~ 170X
180X
60X
SSD: Endurance Data Retention:
10 years without power support MTBF
2 million hours (VS. HDD: 1.6million hours) Wear out
Limit cell write-cycle SLC 100K~1M writes MLC 10K writes
Available space is decreased: downgrade write performance when disk is nearly full
Solutions: Additional reserved space Wear leveling algorithm
to spread write across the whole disk Bad Block Management
map out the bad block
SSD: Capacity Amazing potential on capacity
Could be huge and costly 2.5 Inch: 512 GB 3.5 Inch: 1 TB (BitMacro)
Could be extremely small and inexpensive 4GB SSD for E-PC. Can you image a 10-$ HDD?
0.171.1
2.75
8.6
SATA FC MLC SLC
$/G
B
SSD: Cost
8X
2.48
0.03
FC SLC
$/IO
PS
83X
$ /GB $ /IOPS
SSD Cost: trend
1Q08 2Q08 3Q08 4Q08 1Q09
Cost/GB vsHigh Performance FC
≈40x
≈8x
≈22x
A brief summary
SLC NAND flash is dominant in enterprise environment Advantages:
Excellent performance for Read IO | Random IO | Small IO (<32KB) workload
Low power consumption Small size/weight
Limitations: Cost Endurance Performance downgrade
Alternate routes SSD as cache in server Standalone appliance Tired Storage
SSD in Enterprise Storage
Tired Storage
Cache
Standalone SSD array
SSD Application in Enterprise
BladeCenter HS21
2008 2009 20106
DS8000
3 9 63 9 12
ProLiant Blade, EVA
Blade/Server Unified Storage 7000 ZFS upgrade Storage F5100
USP V/VM
PAM(DRAM) RamSan on V3170
DMX-4 CX-4 2nd Gen SSD FAST
X/Blade/Power SVC
12
EMC
Strategic: Tiered Storage System EFD, FC, SATA
Products: V-Max/DMX-4: CX-4 Celerra
SSD Tuned Arrays will Totally Change the Game!
EMC-FAST (Fully Automated Storage Tiering)
Flash
Fibre Channel
SATA
Flash
SATA
Fibre Channel
V-LUN
V-LUN
Flash
Fibre Channel
SATA
FAST LUN level auto data movement, policy-based Management tools: Ionix (ECC), Navi, and RF
New Q4 2009
V-Max CX-4 Celerra
NetAPP PAM (Performance Acceleration Module)
PCIe card for read cache SW: ONTAP7G, FlexScale, and Predictive Cache Stat.
Add-on SSD array from TMS(Texas Memory Systems) Scale out the read performance for V-series/SAN SW: FlexCache
TMS RamSan 500: 2 TB, DRAM +flash array (RAID)
PAM1: DRAM, up to 16GB/card * 10
PAM2: SSD, up to 512GB/card * 8
SUN/Solaris “Hybrid Storage Pool”
Write IO: write-optimized SSDs (ZFS Intent-log) Read IO: commodity SSDs
Second-level flash cache (L2ARC) behind primary DRAM cache Smart replacement algorithm
18GB*8 100GB * 6
What’s Next in/after SSD? Views from array providers:
EMC: lower cost
IBM: MLC Revolutionary RAM tech?(Racetrack Mem, Phase Change Mem)
Micron, Samsung, Intel, Hynix Intel, JMicron, SandForce, STEC
STEC, Intel, Samsung, Pliant, Segate, Fusion-IO
SUN: MLC SW: to fault tolerant Distinguish write with read IO
Goal: Good Performance + Endurance + Capacity with affordable Cost
Chip Controller Drive
- 34nm- 3 bit MLC- Other NVRAM
- Write leveling algorithm- ECC/RAID/SMART/…- Bad blk map out- SLC+MLC+RAM
How to make best use of SSD?
What’s Next in/after SSD?