Monday Jun 09, 2008
A posting last week, clearly demonstrated that even small increases in utilisations provide HUGE savings".
Then I started looking at the data, it seems that one only really needs two points(!) {active-idle & 100%) to determine the watts used at any utilisation. Let's take a look at the HP DL580 SPECpower_ssj result.
| %util | Measured
Watts | Linear
Predict | watts
diff | %Diff |
| 100% | 387w | - | - | 0% |
| 90% | 376w | 375.4w | 0.6w | 0% |
| 80% | 368w | 363.8w | 4.2w | 1% |
| 70% | 359w | 352.2w | 6.8w | 2% |
| 60% | 347w | 340.6w | 6.4w | 2% |
| 50% | 335w | 329w | 6w | 2% |
| 40% | 322w | 317.4w | 4.6w | 1% |
| 30% | 309w | 305.8w | 3.2w | 1% |
| 20% | 294w | 294.2w | -0.2w | 0% |
| 10% | 280w | 282.6w | -2.6w | -1% |
| idle | 271w | - | - | 0% |
I'll look at more at at other SPECpower_ssj results. But it seems that SPEC should just simply add idle watts and wattage measurements at 100% utilisation to ALL SPEC benchmarks and not redesign benchmarks to measure watts at 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90%. In the worst case, above the linear prediction was ONLY 2% different than actual watts!
I have long said SPEC should just at watt/perf to all of their benchmarks as currently designed.
Disclosure statement
SPECpower_ssj2008:HP Proliant DL580 G5 (4-chip QC Xeon L7345 1.86GHz), 546 overall ssj_ops/watt,
359,523 ssj_ops and 387 watt at 100% target load,
325,931 ssj_ops and 376 watt at 90% target load,
291,991 ssj_ops and 368 watt at 80% target load,
255,512 ssj_ops and 359 watt at 70% target load,
217,222 ssj_ops and 347 watt at 60% target load,
180,262 ssj_ops and 335 watt at 50% target load,
145,079 ssj_ops and 322 watt at 40% target load,
110,173 ssj_ops and 309 watt at 30% target load,
71,409 ssj_ops and 294 watt at 20% target load,
36,070 ssj_ops and 280 watt at 10% target load, and Active Idle 271 watts.
SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation.
Results from www.spec.org as of 12/11/07.
In a more realistic configuration the HP DL580 G5, from HP's own power calculators, a HP DL580 G5 with four QC Xeon 2.93GHz Tigerton and 64 GB memory should draw 1,072watts. HP DL580 power consumption from HP Power Calculator system configured with 4 x2.93GHz processors, redundant PSU, 16 x 4GB DIMMs, 8 x 36GB SAS drives,1 x PCI card, 80% utilisation on 9/10/07: http://h30099.www3.hp.com/configurator/powercalcs.asp
Thursday Jun 05, 2008
Intel's recommendation for 2-socket Xeon QC is 16GB of memory, I'm assuming 4-socket QC is 32GB when I look at this and other docs:
http://www.itworldcanada.com/documents/server-virtualization.pdf
Kingston memory suggests 4-way servers are best for virtualization, see:
www.kingston.com/gov/PDF_files/Kingston_Memory_and_Roadmap.pdf
Actually I've heard 64GB to 128GB being used for many companies for 2-socket to 4-socket consolidation servers.
This fits the memory sizes of most SPEC & TPC performance benchmarks.
What is the one benchmark that vendors only post results on 4GB to 16GB?
SPECpower_ssj. This seems very very very silly to me. Is this an example of vendor self-interest vs. good for the customer? Are vendors trying to not show watts at reasonable memory configs?
Why do I harp on SPECpower_ssj? because it avoids some major issues...
The challenge now ...is not processors. Or power supplies. Or storage. It's memory. Users simply want too much of it. The ratio we're seeing now is the memory taking over [processor power requirements 2 to 1." Roger Schmidt, chief thermal architect and DE of IBM server and workstation division - Computer World April 30, 2007
I think small-memory on servers is generally silly, I even know people who are buying 4GB laptops. You can't convince me that 4GB servers are the way to go for most commercial uses...
SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation. Results at www.spec.org
Wednesday Jun 04, 2008
Servers are very different than laptops, DUH! Therefore one must benchmark power
in a very different way. We all know that laptops spend lots of time
at low utilisation or idle (waiting for your input). Most servers
should not be used at idle or anywhere near idle. Kick out any vendor
that only wants to show watt savings at low utilisation, they are trying to
get you to take your eye of the real truth.
In the good ol' wasteful days of yore, you could have your servers running at 20%, drive your huge SUV alone down the block to pick up buy an incandescent bulbs.
Today, you need to lower your costs and carbon footprint by turning off wasteful low-utilised servers, buying efficient servers and running them in at least an efficient part of the power curve, say 50-60% util or more.
Demand that every vendor add power measurement to every benchmark right now!
I fear many are redesigning benchmarks to add power only to emphasize low utilisation. In my opinion (I speak for myself not necessarily Sun), low utilisation measurements are just smoke and mirrors and disinformation. As I pointed out last week you can save many times more watts per unit of work by just raising your utilisation a bit.
Why do I mention this which appears obvious...
This morning I had breakfast with a friend. Always enjoyable catching up with friends. He mentioned that a customer of his wanted to make buying power decisions "based on the idle watts of a server"!?! The customer was prompted to ask that by a vendor. After a realistic conversation continued the customer now feels completely mislead by the other vendor. , you lost.
Now off to a tasty lunch...
Friday May 30, 2008
The SPECpower_ssj2008 benchmark goes out of its way to measure servers at low-utilisation (5 of 11 datapoints are in the wasteful active-idle to 40% range - the worst range for servers). SPECpower_ssj actually shows this. Customers needs to demand that power measured on all benchmarks, now.
Let's look at HP DL580 G5 4-socket (for SPECpower_ssj2008 HP only used the low-GHz 1.86GHz Xeon, tiny 16 GB with special DIMMs, and a hacked non-standard BIOS). Regardless it can still be used to prove my point.
Increasing utilisation even a small amount provides HUGE improvements in watts-per-unit-of-work. Increasing utilisation a tiny 10% improve your watt/work an amazing 33-163% ! If you increase utilisation more you save even more:
| %Util Improvement | Savings in watts-per-unit-of-work |
| 10 | 33-163% |
| 20 | 45-257% |
| 30 | 62-353% |
<| 40 | 84-437% |
| 50 | 114-511% |
| higher% | even more! |
The biggest savings occur when you stop running at low utilisation.
We need to do everything we can to discourage low-utilisation!
The first column, in the table below, is the %utilisation you start at, the rows than show you the %savings if you increase your utilisation. So for example if you were at 20% utilisation (2nd row from the bottom) and increase the %utilisation to 40% (3rd column from the right) you save 140% per unit of work!
| %u | Perf/Power | 100% | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% |
| 100% | 929 | | | | | | | | | |
| 90% | 867 | 33% | | | | | | | | |
| 80% | 793 | 45% | 35% | | | | | | | |
| 70% | 712 | 62% | 50% | 37% | | | | | | |
| 60% | 626 | 84% | 71% | 56% | 41% | | | | | |
| 50% | 538 | 114% | 99% | 82% | 64% | 46% | | | | |
| 40% | 451 | 155% | 138% | 117% | 96% | 75% | 54% | | | |
| 30% | 357 | 223% | 200% | 174% | 148% | 121% | 94% | 64% | | |
| 20% | 243 | 374% | 341% | 303% | 264% | 224% | 185% | 140% | 89% | |
| 10% | 129 | 793% | 731% | 659% | 586% | 511% | 437% | 353% | 257% | 163%
| |
IBM bloggers accuse me of many things. LET ME BE CLEAR: These are my personal opinions and NOT the opinions of Sun. This blog is NOT the source for official opinions.
Disclosure statement
SPECpower_ssj2008:HP Proliant DL580 G5 (4-chip QC Xeon L7345 1.86GHz), 546 overall ssj_ops/watt,
359,523 ssj_ops and 387 watt at 100% target load,
325,931 ssj_ops and 376 watt at 90% target load,
291,991 ssj_ops and 368 watt at 80% target load,
255,512 ssj_ops and 359 watt at 70% target load,
217,222 ssj_ops and 347 watt at 60% target load,
180,262 ssj_ops and 335 watt at 50% target load,
145,079 ssj_ops and 322 watt at 40% target load,
110,173 ssj_ops and 309 watt at 30% target load,
71,409 ssj_ops and 294 watt at 20% target load,
36,070 ssj_ops and 280 watt at 10% target load, and Active Idle 271 watts.
SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation.
Results from www.spec.org as of 12/11/07.
In a more realistic configuration the HP DL580 G5, from HP's own power calculators, a HP DL580 G5 with four QC Xeon 2.93GHz Tigerton and 64 GB memory should draw 1,072watts. HP DL580 power consumption from HP Power Calculator system configured with 4 x2.93GHz processors, redundant PSU, 16 x 4GB DIMMs, 8 x 36GB SAS drives,1 x PCI card, 80% utilisation on 9/10/07: http://h30099.www3.hp.com/configurator/powercalcs.asp
Friday May 16, 2008
Sun has shown watts on UltraSPARC for years!:
2008: UltraSPARC T2+
2007: UltraSPARC T2
2005: UltraSPARC T1 & T2000 blogs with power-performance
Sun is now showing measured watts with measured performance for X64 servers as well, the rumor mill inside Sun is saying we are going see a lot more soon:
2008: X64 Virtualization
2008: X64 Java
Real measured watts on a variety of workloads is critical to truly inform customers.
Thursday May 08, 2008
Yet another SPECpower_ssj of a "different" configuration:
- tiny memory: ONLY 4GB!
- low GHZ CPU: only 2.83GHz QC
- tiny config: only 1 chip!
Why do the servers that vendors publish on SPECpower_ssj2008 look so different from servers used on other benchmarks? See, this is the problem with NOT adding perf/watt on every benchmark as published. What can the industry learn from low-GHz small-memory configurations?
I a previous posting I mentioned that HP configurations used in other benchmarks have reasonable-sized memory and high-GHz CPUs, I'll dig up the same on IBM, or you can just look at the www.spec.org website yourself:
64GB: HP DL580 G5 (4 quad-core Xeon 2.933GHz)
64GB: HP DL585 G2 (4 dual-core Opteron 3GHz)
32GB: HP DL380 G5 (2 quad-core Xeon 2.66GHz)
32GB: HP DL380 (2 quad-core Xeon 3GHz)
32GB: HP BL685c (4 dual-core Opteron 3GHz)
32GB: HP BL460c (2 quad-core Xeon 3GHz)
for more see: http://blogs.sun.com/bmseer/entry/hp_dl580_g5_4_qc
It is so easy to measure watts on benchmarks that one publishes, Sun does it all of the time. Why other vendors not disclose their measured system wattages"
Sun has shown them on UltraSPARC for YEARS!:
2008: UltraSPARC T2+
2007: UltraSPARC T2
2005: UltraSPARC T1 & T2000 blogs with power-performance
...and Sun is starting to show them on X64.
Disclosure statement:
IBM System x3200 M2 server achieved a Performance to Power Ratio of 1,054 overall ssj_ops/watt (one-chip quad-core Intel Xeon Processor X3360 (2.83GHz, 1 chip, 4 cores, 4 cores per chip, 2x6MB L2 cache, and 1333 MHz front-side bus), 4GB of DDR2 PC2-5300 FBD memory, IBM JavaTM 6 Runtime Environment, Microsoft Windows Server 2003 R2 Enterprise x64 Edition SP1. SPEC and the SPECpower are registered trademarks of the Standard Performance Evaluation Corporation. All results from www.spec.org as of 5/08/08.
Note: I got this info from the IBM website, as the report isn't up on SPEC.org yet. We'll all have to wait to find out measured watts @100% util on the 1-chip with only 4GB (!) configuration mentioned above. IBM didn't mention this in any of the press info or blogs.
Also how come no one jumps on IBM for lack of proper SPEC copyright information? IBM bloggers write:
SPEC and the SPEC benchmark names are registered trademarks of the Standard Performance Evaluation Corporation.
Wednesday Apr 30, 2008
Sun continues to show watts on a wide variety of benchmarks, first on
UltraSPARC T1, T2, T2 Plus benchmarks on all kinds of SPEC benchmarks that don't require it! ...and Sun extends this to X64 on VMmark benchmark. Other vendors need to do the same!
I didn't know about this benchmark until I saw it here (personally I hope Sun continues to show Watt/performance data on everything, hint hint for the internal people): http://blogs.sun.com/ontherecord/entry/ibm_sun_fire_x4450_tops
4-chip 2.93GHz Quad-Core Intel Xeon, 64GB, standard BIOS: VMmark = 830watts
The Sun Fire X4450 server, running VMware Virtual Infrastructure 3 software, posted one of the best scores among all 16 core results – 12.23 @ 8 tiles, with an average power consumption of only 830W measured during the steady state of the benchmark.
Sun used a 64GB configuration, which makes sense because virtualisation is driving up memory sizes. Table with the current 4-socket 16-core results which all use 64GB of memory (4/28/08)
| System |
Sk/Cr/Th |
Clock/CPU |
ESX |
watts |
Tiles |
Score |
| IBM x3850 M2 |
4/16/16 |
2.93 Xeon7350 |
3.5.0 |
? |
9 |
13.16 |
| Sun Fire X4450 |
4/16/16 |
2.93 Xeon7350 |
3.5.0 |
830w |
8 |
12.23 |
| Dell PE R900 |
4/16/16 |
2.93 Xeon7350 |
3.5.0 |
1325w
watt calc |
8 |
12.23 |
| HP DL580 G5 |
4/16/16 |
2.93 Xeon7350 |
3.0.2 |
1086w
watt calc |
8 |
11.54 |
More details and results at:
http://www.vmware.com/products/vmmark/results.html
The Sun wattage measured on 2 hours benchmark steady state:
Watts: min=788watt, max=850watts, avg=830watts.
In reality with the same CPU, and memory configuration, I really don't expect actual measured to be much different, but it would help if HP and Dell actually published measured watts.
Watt calc:
Dell's public power information on CPU & memory configurations
used in their VMmark submission is from the Dell's Datacenter Capacity Planner found on this web site http://www.dell.com/content/topics/topic.aspx/global/products/pedge/topics/en/config_calculator?c=us&cs=555&l=en&s=biz) This shows a power consumption estimate of 1325watts using "Typical SPEC workload" (it is even higher with "Scientific" workload).
Watt calc:
HP's only public power information on CPU & memory configurations
used in their VMmark submission is from the HP power calculator (http://h30099.www3.hp.com/configurator/powercalcs.asp). The tool produced power requirement of 1086watts at 115V with 95% CPU utilisation.
...but you get very different watts when you change the frequency, memory-size, and an very different power benchmark (can't compare SPEC to non-SPEC benchmarks).
4-chip 1.86GHz Quad-Core Intel Xeon, 16GB hacked BIOS: SPECpower_ssj2008 = 387 watts at 100% target load
Reading "HP ProLiant DL580 G5 server posts highest 4P result on the new SPECpower_ssj2008(TM) benchmark" brochure leaves one quite confused. HP does not specify processor GHz, Memory size, or the use of non-standard BIOS - why?. Take note SPEC members: you guys need to force that be clearly specified in the future, or you will just encourage confusion.
Also why doesn't HP benchmark four 2.93GHz QC with 64GB of memory with default (normal) BIOS settings? So the industry can see the wattage difference vs 1.86GHz QC with 16GB memory. The 2.93GHz QC 4-chip results (with 32GB to 64GB with normal BIOS) exist on performance benchmarks they should also exist on power-performance benchmarks.
I'd suggest SPEC require better disclosure of information and clearly show effects of CPU GHz and memory size. MEMORY SIZE makes a HUGE difference in watts. Again I plea to add power measurements and power-performance metrics to all performance benchmarks at full utilisation.
SPEC Disclosure statement
SPECpower_ssj2008: HP Proliant DL580 G5 (4-chip QC Xeon L7345 1.86GHz, 16GB), 546 overall ssj_ops/watt, 359523 ssj_ops and 387 watt at 100% target load, 255512 ssj_ops and 359 watt at 70% target load, and 71409 ssj_ops and 294 watt at 20% target load. SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation. Results from www.spec.org as of 12/11/07.
Issues?
http://blogs.sun.com/bmseer/entry/specpower_ssj2008_power_benchmark_needs
http://blogs.sun.com/bmseer/entry/hp_dl580_g5_4_qc
Wednesday Jan 09, 2008
It is so easy to measure you wonder why some vendors hide their wattages.
Sun as US T2:
2007: UltraSPARC T2
2005: UltraSPARC T1 & T2000 blogs with power-performance
The only thing I can think of is that the numbers are embarrassing in
real configurations.
I a previous posting I mentioned that HP configurations used in other benchmarks have reasonable sized memory:
64GB: HP DL580 G5 (4 quad-core Xeon 2.933GHz)
64GB: HP DL585 G2 (4 dual-core Opteron 3GHz)
32GB: HP DL380 G5 (2 quad-core Xeon 2.66GHz)
32GB: HP DL380 (2 quad-core Xeon 3GHz)
32GB: HP BL685c (4 dual-core Opteron 3GHz)
32GB: HP BL460c (2 quad-core Xeon 3GHz)
Looking around at HP's own power calculators we find that an
HP DL580 G5 with four QC Xeon 2.93GHz Tigerton and 64 GB memory
should draw 1,072watts but how much does is actually draw?
We carefully measured one in our lab running database workloads at
60-80% util at just above 800watts. Fair, NO gaming. It is so easy to
do this right, try it yourself.
Note:HP configures 1200w supplies with their 4 Xeon QC DL580 G5. Everyone
knows that even with efficient power supplies you
design near the rating so that you keep the costs down and keep the
efficiency up. An engineer would be a bit daft to put a 1200w supply on a
server they expect to draw only 300watts! 
HP DL580 G5 power consumption from HP Power Calculator system configured with 4 x2.93GHz processors, redundant PSU, 16 x 4GB DIMMs, two GbE, four 146GB SAS disks, two PCI-E Dual-Port FC, 80% utilisation on 1/8/07: http://h30099.www3.hp.com/configurator/powercalcs.asp
Tuesday Jan 08, 2008
Memory size is one of the most important configuration details you need to know
when comparing measured server watts. This has been true for a long time.
In 2006 I dug into the actual watts used by 2-socket Woodcrest Xeon servers.
Woodcrest:
330 watts 2-socket 8GB
430 watts 2-socket 16GB
510 watts 2-socket 32GB
Now we have even lower-watt CPUs that have a lot more power management to reduce
CPU watts, which means in general that memory size will matter even more in the future.
Another fact is that all of the servers I see using virtualization are being configured
with larger and larger memory (32GB to 128GB for 2-socket servers!).
This is why I'm not overly impressed with wattage measured on small-memory configurations like
8GB or 16GB.
Thursday Jan 03, 2008
Luiz André Barroso and Urs Hölzle of Google have written an article called:
The Case for Energy-Proportional Computing. You can find the IEEE Computing article here.
They correctly point out that memory (and disk) are a key factor in power used. Too bad that new SPECpower benchmark only favors tiny-memory configurations, and vendors do not publish measured watts on real-size memory configurations.
They miss the fact that low utilization wastes more power than energy-proportional designs will get them,
as we've pointed out
here
Disclosure statement
SPECpower_ssj2008. SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation. See www.spec.org.
Tuesday Dec 18, 2007
A new SPEC benchmark called SPECpower_ssj2008 was announced last week..
I've taken a little time to look at the new results and benchmark rules.
Quite simply, I don't know why SPEC didn't add power measurement
to every benchmark. It is quite easy to add rules that
puts one SUT (system under test) on a power meter and a few rules
to accurately measure power. That should have been done months ago,
it is so much easier than creating a new benchmark.
So why didn't SPEC do this? I have no idea. I can only guess some
vendors to show off their power-management software at different utilisation
levels. As we've talked about here for a very long time, running servers at low-utilisation (below 50% utilisation) is the worst way in the world to waste power... Even with the most extreme power-saving HW/SW.
With a different benchmark only for power-benchmarking it is really possible
to game results. Did anyone?
- HP submitted a SPECpower_ssj2008 on the DL 580 G5 QC Xeon. Cool
now we can see what the DL580 G5 does. But HP PICKED 1.86GHz Xeon L7345 for
SPECpower_ssj and a very DIFFERENT processor (2.9GHz Xeon) for performance on SPECweb2005, well at least they are not confusing things...
- HP's DL 580 G5 SPECpower_ssj2008 documentation does NOT EVEN mention processor GHz or type!
Why?
- The only SPECpower_ssj2008 results were on 4GB, 8GB, 16GB configs.
Memory is a huge power draw. So why configure such small systems for power?
Why do these vendors use 32GB and 64GB configs on performance benchmarks?
- The HP DL580 G5 used one 60GB 5400 RPM SATA drive. My laptop has better
- HP's DL580 G5 Power supplies used are 2x1200 watts. The 1.86GHz
Xeon DL580 G5 draws 387 watts at 100% on SPECpower_ssj2008.
Since all vendors know that you use power supplies near their rating
for best energy efficiency, why does HP not sell properly-size power supplies?
Maybe because HP typically expects to sell configurations that are different
than SPECpower_ssj2008 DL580 configs?
- Is running at low utilisation efficient? SIMPLE answer NO!
Let's look at SPECpower-ssj2008 HP DL580 G5. Comparing 70% utilisation
with 20% utilisation we see that one wastes 3 TIMES more watts for the
same amount of work at 20% utilization than at 70% utilization!!! 3 = round(2.93) = (294w/71409ssj_ops) / (359w/255512ssj_ops)
- SPECpower_ssj allows default BIOS settings to be changed to make better
results by turning off prefetch (also see SPECjbb & prefetch) - yeah, right, every customer does that
get real.
So what serves the industry? Using the same configurations that you
benchmark for performance and power-performance.
Sun does this and has been doing this for years:
2007: UltraSPARC T2
2005: UltraSPARC T1 & T2000 blogs with power-performance
The only thing I really can take away from SPECpower_ssj2008 is that running at low utilization is silly, read carefully, and avoid silly configurations.
Disclosure statement
SPECpower_ssj2008: HP Proliant DL160 G5 (2-chip QC Xeon E5450 3GHz), 698 overall ssj_ops/watt. SPECpower_ssj2008:HP Proliant DL580 G5 (4-chip QC Xeon L7345 1.86GHz), 546 overall ssj_ops/watt, 359523 ssj_ops and 387 watt at 100% target load, 255512 ssj_ops and 359 watt at 70% target load, and 71409 ssj_ops and 294 watt at 20% target load.
SPECpower_ssj2008: Colfax CX2266-N2 (2-chip AMD Opteron DC 2216HE 2.4GHz), 203 overall ssj_ops/watt. SPEC, SPECpower reg tm of Standard Performance Evaluation Corporation.
Results from www.spec.org as of 12/11/07.
HP ProLiant DL580 G5 (16 cores, 4 chips) 30261 SPECweb2005. SPEC, SPECweb reg tm of Standard Performance Evaluation Corporation. Results from www.spec.org as of Oct 8, 2007.
HP DL580 power consumption from HP Power Calculator system configured with 4 x2.93GHz processors, redundant PSU, 16 x 4GB DIMMs, 8 x 36GB SAS drives,1 x PCI card, 80% utilisation on 9/10/07: http://h30099.www3.hp.com/configurator/powercalcs.asp HP DL385G2 power consumption from HP Power Calculator for system configured with 2 x AMD 2220 2.8GHz processors, redundant PSU, 8 x 4GB DIMMs, 2 x HBAs and 2 x 146GB SAS drives, 80% utilisation on 6/4/07: http://h30099.www3.hp.com/configurator/powercalcs.asp
Wednesday Sep 26, 2007
I'm seeing lots of bad comparisons abound in articles and tech analyst reports
around pricing and power.
I see them talking about system price by only referring to processor/cores, and then...
- not specifying memory size, or using lowest cost slow memory size
- not configuring reasonable size fast memory
- not specifying GHz (or talking Speed of at one GHz and cost of another)
I see them talking about importance of system wattage by only referring to processor TDP (Thermal Design Power of the chip, yes ignoring the whole system, making people assume the rest is all the same, which it isn't), and then...
- not specifying system wattage
- not configuring reasonable size fast memory
- not specifying wattage on actual performance benchmark runs.
included above are hints on how they can fix them.
Tuesday Sep 25, 2007
The BBC reports that "Large majorities in many countries now believe human activity is causing global warming, a BBC World Service poll suggests."
It goes on to say, "A sizeable majority of people agreed that major steps needed to be taken soon to address global warming."
More at: http://news.bbc.co.uk/1/hi/world/7010522.stm
Friday Sep 14, 2007
I know AMD & Intel love to focus on the power used by CPUs
in their high-stakes battle to gain server chip dominance. Both
started talking TDP (Thermal Design Power) and getting people to judge
systems based on TDP.
...wait a minute, buying a system based on the power of a CPU is
a bit of misdirection unless the CPU is most of the power. This isn't
the case any more. So CPU TDP should be ignored, unless you are
designing your own product and are just buying CPUs.
First of all system power is what datacenters care about, so Intel and
AMD should be talking about system power in realistic memory configurations.
Memory draws lots of power these days.
Second,TDP was created so the manufactures of servers manufacturers
would know much power the chip consumes in worst-case maximum-power cases
so they could design power supplies, cooling, etc. That just isn't
useful to datacenter managers.
AMD's marketing only slightly improved the situation by telling
customers of SYSTEMS to look at the processor's ACP (Average CPU
Power).
Two problems:
- Focus on CPU power to avoid talking system power, but system power is
what one needs to know, in average case to estimate electrical bills.
- Focus on average CPU power not server maximums that datacenters need
to design cooling on (see: http://blogs.sun.com/bmseer/entry/watts_a_matter_with_their.
ACP of a CPU ...hmmm, do you know what a pain it is to just measure a CPU. AMD
in their whitepaper , has to isolate the power consumed by the processor
and that consumed by the motherboard -- this requires motherboard modifications and special instrumented server platforms!.
way to much work to get a marketing message, all we want is server power on a variety of memory configuations and full-speed CPUs and actually running at good datacenter utilizations!
WARNING: Everyone loves to talk performance of high-GHZ CPUs and low-power of low-GHz CPUs, so watch for the confusing marketing and much worse "bait&switch." Also watts per core is useless marketing, it is the watt/perf for a system that counts. Also any vendor trying to sell power-efficiency on high-performance
systems should report watt/performance along with their world record performance on that system.
Tuesday Sep 11, 2007
Huge reductions can be made in datacenters with existing technology by just changing a few datacenter practices & metrics!
Things that make a HUGE difference (factors = big percentages):
- Turn off un-used servers, figure out how to turn more off
- Drive up utilisation up to 60% utilisation on all servers (this can decrease power by a factor of THREE TIMES (even if you have the latest power throttling chip features!)
- If you need virtualisation software to drive up the utilization get it, but make sure it is very efficient no overhead virtualisation like Solaris zones.
Remember CPU overhead means your are burning watts, or at least measure the CPU overhead on your virtualisation software to pick the most efficient alternative.
- Put the datacenters utility bill in the IT department! Motivate people!
- ...spread the word, as this knowlege virally spreads larger and larger number of people get this happening in their datacenters!
Remember if you save watts at the server you save watts to cool it, and
also save the inefficiences of getting the electricity from the powerplant to the datacenter! http://blogs.sun.com/bmseer/entry/power_from_utility_to_servers
Things that make some Difference (percentages):
- datacenter layout (5-10%)
- More efficient airflow & air conditioning (maybe 10-20%)
- tune your application performance, the faster it goes the more efficiently it goes
What to measure:
server-watt/perf (just like $/perf), perf/watt is misleading!
judge servers by full configuration power utilisation
compare servers of the same memory size (more important that processor count)
IT budget improvements (HW, SW, & Utility bills).
more details at: http://blogs.sun.com/bmseer/entry/eco_actual_fancy_power_saving
...everything above this was above the line!
Below the line.
What NOT to measure:
- Do NOT judge which server to buy by the TDP of the processor --- it is the whole server st*pid
- Do NOT judge which server to buy by the in-lab measurements of the CPU-only --- it is the whole server st*pid
- perf/cpu-watt is misleading, use server-watt/perf (just like $/perf)
- Do NOT assume perf/watt is server metric, you must ask!
- Do NOT compare servers at 30% utilization, that is like judging which
commuter car to buy by looking at vendor stats that compare overloaded SUV uses less gas going up a 20% road grade?!? -- you need to look at the full-memory config/CPU MHz you are buying at the good utilization 60% or more that you should be running your datacenter at!
- Do NOT judge which server to buy by looking at performance of fastest GHz CPUs at full utilization & full memory and then judging energy efficiency of low-GHz CPUs at 30% utilization and small memory. All benchmarks should have measured server watt/perf on every SPEC & TPC benchmark.
I think the above hints are much more useful than the following story:
http://www.cnn.com/2007/TECH/biztech/09/08/tech.green.credentials.ap/
final note:
Now go home and buy some CFLs, and turn off your lights when not in use...
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