Download Keeping Hot Chips Cool

Keeping Hot Chips Cool
Thermal Management for Green
Computing
Yang Ge
Professor Qinru Qiu
utline
• Background
– Need for green computing
– Adverse effects of high temperature
– Thermal management techniques
• Ongoing project
– Power and thermal management for single chip
cloud computer (SCC)
The need for green computing
• Computers consume 3% of
US energy use
– Saving 1% of energy of
data center is more than
saving a power plant
• Each computer generates
1 ton of CO2 every year
– Equivalent to the CO2
emission of a car driving a
round trip between New
York and Los Angeles
Power and Cost for Cooling
Systems
• The energy dissipation for
cooling system is high
– Cooling fan power can reach up
to 51% of the overall server
power budget
• The cooling cost is
expensive in large data
centers
– The total cooling costs for
large data centers can run into
tens of millions of dollars
Other 6%
Fans
Mem 20%
CPU
Fans 51%
Mem
Other
CPU 24%
IBM P670 Server power breakdown
Adverse effects of high
temperature to VLSI Chips
• Affects the system
reliability and causes
permanent device failure
• Doubles leakage power
consumption every 9oC
increase
• Requires to increase
fan speed which could
reduce fan life time
Thermal Management Techniques
Offline Techniques
Temperature aware
scheduling
Dynamic voltage
frequency scaling
Online Techniques
Temperature aware
task migration
Ongoing Project
• Power and thermal management for single
chip cloud computer (SCC)
Overview of SCC Architecture
• 24 tiles arranged
in 6X4 arrays
• 2 CPUs on each
tile
• A router
associated with
each tile
• 4 memory
controllers go to
on board memory
Management Console PC (MCPC)
• SCC and MCPC
communicates
over PCIe bus
• MCPC runs
Ubuntu 10.04 x64
and SW from
Intel
• Load Linux image
on each core
• read and modify
SCC registers
• Load programs on
the SCC cores.
Power and Thermal Management
• 6 voltage domains
• 24 Frequency domains,
one for each tile
• 2 temperature sensors
on each tile
• Voltage and frequency
can be changed
separately on each
domain
hank y u