25-08-2017, 09:32 PM
IRAM: A Microprocessor for the Post-PC Era
[attachment=34553]
Perspective on Post-PC Era
PostPC Era will be driven by 2 technologies:
1) Mobile Consumer Devices
e.g., successor to PDA, cell phone, wearable computers
2) Infrastructure to Support such Devices
e.g., successor to Big Fat Web Servers, Database Servers
A Better Media for Mobile Multimedia MPUs: Logic+DRAM
Crash of DRAM market inspires new use of wafers
Faster logic in DRAM process
DRAM vendors offer faster transistors + same number metal layers as good logic process? @ ≈ 20% higher cost per wafer?
Called Intelligent RAM (“IRAM”) since most of transistors will be DRAM
IRAM Vision Statement
Microprocessor & DRAM on a single chip:
on-chip memory latency 5-10X, bandwidth 50-100X
improve energy efficiency 2X-4X (no off-chip bus)
serial I/O 5-10X v. buses
smaller board area/volume
adjustable memory size/width
Potential Multimedia Architecture
“New” model: VSIW=Very Short Instruction Word!
Compact: Describe N operations with 1 short instruct.
Predictable (real-time) performance vs. statistical performance (cache)
Multimedia ready: choose N*64b, 2N*32b, 4N*16b
Easy to get high performance
Compiler technology already developed, for sale!
Don’t have to write all programs in assembly language
IRAM Chip Challenges
Merged Logic-DRAM process: Cost of wafer, Impact on yield, testing cost of logic and DRAM
Price of on-chip DRAM vs. separate DRAM chips?
Time delay of transistor speeds, memory cell sizes in Merged process vs. Logic only or DRAM only
DRAM block: flexibility via DRAM “compiler” (very size, width, no. subbanks) vs. fixed block;
synchronous interface available?
Applications: advantages in memory bandwidth, energy, system size to offset above challenges?
Infrastructure for Next Generation
Servers today based on desktop MPUs: Central Processsor Units + Peripheral Disks
What would servers look like if based on mobile, multimedia microprocessors?
Include processor, network interface inside disk
ISTORE: a HW/software architecture for building scaleable, self-maintaining storage
An introspective system: processor/disk it monitors itself and acts on its observations
No administrators to configure, monitor, tune
[attachment=34553]
Perspective on Post-PC Era
PostPC Era will be driven by 2 technologies:
1) Mobile Consumer Devices
e.g., successor to PDA, cell phone, wearable computers
2) Infrastructure to Support such Devices
e.g., successor to Big Fat Web Servers, Database Servers
A Better Media for Mobile Multimedia MPUs: Logic+DRAM
Crash of DRAM market inspires new use of wafers
Faster logic in DRAM process
DRAM vendors offer faster transistors + same number metal layers as good logic process? @ ≈ 20% higher cost per wafer?
Called Intelligent RAM (“IRAM”) since most of transistors will be DRAM
IRAM Vision Statement
Microprocessor & DRAM on a single chip:
on-chip memory latency 5-10X, bandwidth 50-100X
improve energy efficiency 2X-4X (no off-chip bus)
serial I/O 5-10X v. buses
smaller board area/volume
adjustable memory size/width
Potential Multimedia Architecture
“New” model: VSIW=Very Short Instruction Word!
Compact: Describe N operations with 1 short instruct.
Predictable (real-time) performance vs. statistical performance (cache)
Multimedia ready: choose N*64b, 2N*32b, 4N*16b
Easy to get high performance
Compiler technology already developed, for sale!
Don’t have to write all programs in assembly language
IRAM Chip Challenges
Merged Logic-DRAM process: Cost of wafer, Impact on yield, testing cost of logic and DRAM
Price of on-chip DRAM vs. separate DRAM chips?
Time delay of transistor speeds, memory cell sizes in Merged process vs. Logic only or DRAM only
DRAM block: flexibility via DRAM “compiler” (very size, width, no. subbanks) vs. fixed block;
synchronous interface available?
Applications: advantages in memory bandwidth, energy, system size to offset above challenges?
Infrastructure for Next Generation
Servers today based on desktop MPUs: Central Processsor Units + Peripheral Disks
What would servers look like if based on mobile, multimedia microprocessors?
Include processor, network interface inside disk
ISTORE: a HW/software architecture for building scaleable, self-maintaining storage
An introspective system: processor/disk it monitors itself and acts on its observations
No administrators to configure, monitor, tune