Gee I dont know, at my one job we still have some 9500's and a 7100 with a 266Mhz G3 upgrade, these have been running 8 hours a day all week since like 1996. I still have my PowerCenter 132 with a 500Mhz G3, it runs fine. I could try and run OS X on these, but why bother?
Don't even start on upgrade path. You paid 300 bucks for a 266 mhz sonnet card when you could have paid 200 bucks for a Ghz+ processor and motherboard. You ain't going to make it far on a 266mhz G3 on a 50mhz bus.
For $3500 new mac prices, you can buy a complete new system every 9 months for 5 years.
Macs HAD good hardware. Apple stopped funding hardware upgrades when they started on OS X. Now they have a great OS and crap hardware.
It's not your fault. They are just significantly behind. OS X is not "slow". the fucking hardware is.
10 inch diameter 25 pound carbon fiber flywheel at 36,000 rpm.
Edge speed is 1071 Miles per hour.
A "flander" is a large splinter that explodes off the inside of a ship's hull when a cannon ball hits broadside at sub-sonic velocities. Thus the term "smash to flanders".
a 25 pound cannonball will completely breach 8 inches of wood creating a manticore of wood splinter shrapnel.
A tornado will drive pieces of straw through a wall at subsonic speeds.
A winch cable will crack at supersonic speeds if it snaps. A winch cable will shear an engine block.
100 lashes is a death penalty.
Kinetic Energy = 1/2*I*w*w
I = moment of inertia --> ability of an object to resist changes in its rotational velocity
w = rotational velocity (rpm)
I = k *M*R*R (M=mass; R=Radius); k = intertial constant (depends on shape)
Inertial constants for different shapes:
Wheel loaded at rim (bicycle tire): k =1 solid disk of uniform thickness; k = 1/2
I assumed 4/5 because of the design they used
Kinetic Energy of flywheel = 68,428,800 Joules
357 Magnum = 937 Joules.50 cal sniper rifle = 16,539 Joules
4000 sniper rifle bullets worth of energy exploding outward in the form of tiny splinters of a substance that happens to have one of the highest tensile strengths. Assume 98% of the kinetic energy is lost to heat. 80 sniper bullets.
"Every time I've done this comparison, the Mac was about %10 cheaper, and usually still had extra stuff."
Compare again.
You took the sucker's position. cut-n-paste:
http://www.heise.de/ct/english/02/05/182/
http://www.digitalvideoediting.com
"Benchmark Duel: Mac vs. PC, Round II"
http://www.teamlambchop.com/bench/303results.htm
(the dual G4 1Ghz is in 207th place @ 7 hrs 7 minutes, right behind the dual 933mhz PIII which is 3 minutes faster. Top place is held by an Athlon @ 2 hrs 48 minutes.)
If the 733 G4 is not as fast as the 1Ghz PIII, as Carmack stated, how do you expect the Dual G4 1Ghz to compete with a dual 1733 Athlon or Dual 2.2 Ghz Xeon?
The Mac can't even use a professional graphics card like the Quadro 900XGL or 3D Labs Wildcat III 6210. No usb 2.0. PCI bus limited to 180 MB/s. No DDR memory in their workstations. 133fsb G4 can't take advantage of DDR anyway. Insane priced monitors using old flat panel technology. Is lack of hardware support a "feature"?
Open your EYES becausethe only "extra stuff" in a mac is price!
No, my posts are not always popular. I'm a Mac user, remember.
Feeling like martyring yourself on the mac sword? Do you use them just because you percieve them to be unpopular?
"Well, since their hardware already outperforms (MTBF, useable life, ROI) nearly all x86 hardware out there, I'd say they have a good head start.
"Informed dialog? I'm ready when you are"
No, you are not ready. You took the sucker's position. cut-n-paste:
http://www.heise.de/ct/english/02/05/182/
http://www.digitalvideoediting.com/cgi-bin/getfr am eletter.cgi?%2F2002%2F05_may%2Ffeatures%2Fcw_aesho wdown.htm
http://www.digitalvideoediting.com/cgi-bin/getfr am eletter.cgi?%2F2002%2F05_may%2Ffeatures%2Fcw_aesho wdown.htm
http://www.teamlambchop.com/bench/303results.htm
(the dual G4 1Ghz is in 207th place @ 7 hrs 7 minutes, right behind the dual 933mhz PIII which is 3 minutes faster. Top place is held by an Athlon @ 2 hrs 48 minutes.)
Return on Investment: Paying SEVEN TIMES AS MUCH for a computer that is HALF AS FAST
Usable life: what is the usable life on a computer that is 2 years obsolete when you purchase it? Where did the "5 year mac" go?
Mean time between failure: based purely on OS X's upgrade cycle and time to install upgrades give you 99.8% reliability. But the spinning beach ball of death adds another few hour a year down. 99.6%. Then the CD won't eject and is now missing the paperclip hole. 99.5%. Then the printer stops responding, reboot again 99.4%. This app needs 9.2 to run, classic is no go 99.1% Cracked hinges on case 1 week down 97%.
Not exactly 5 nines. Not even 2 nines. In fact, that is a 9 and a 7.
MTBF is less than 2 weeks. Better than win98. Not as good as straight FreeBSD. About the same as Win2K. Wonderful. Just as reliable as an OS with 64,000 bugs.
These forums are not about gaining karma. These forums are about speaking the truth, opening an informed dialogue and not shying away from contentious issues.
Obviously, your only intent is to preserve your precious karma. You only say what you know will be popular. The consummate politician. Your posts are popular but are filled with nothing but populist drivel. You have never taken a stand for anything you believe in. You only parrot the party line.
Spineless.
Whoa, dude! My Karma is, like, "Excellent"!
We don't care.
This is a discussion, not a popularity contest.
Karma does not get you elected.
Your focus on karma at the expense of the discussion is sad.
You own a Mac.
I own 180 Macs.
Their cost is non-trivial.
Their performance is substandard.
Their OS is the best on the market.
You are likely to be content with your mac's performance.
I could care less.
Apple will not get another dime from me untill their harware is held to the standard their OS is.
Even Steve Jobs prefers the performance of x86 over PowerPC. Pixar uses x86 linux clusters.
I thought of this years ago. Then realized I was wrong. How much power does your local AM radio station put out? 50,000 watts. Will the ammount of power required to broadcast to three states ever drop? Nope. How many 50,000 watt radio stations are there in the US alone? Over 8000.
Will XM sattelite radio change that? Has linux been able to break Microsoft's monopoly?
Really needs a good flight model. Stopping to turn is annoying. Foward and reverse need keys with mouse look, reverse x,y axis. Would also be nice to be able to select pairs of stars and get distance data between them. Constellations would be nice too... sort of a stargate style. A "what does orion look like from polaris" sort of thing.
So what you are really saying is OS X can't walk and chew gum at the same time... No, OS X has no trouble prioritizing background tasks. Running a distributed net client would not affect it in the slightest. Since a single Mac could never hope to host a tier 1 pr0n site, I'm going to assume that was a joke.
Video card has no bearing on render time. Rendering is done by the CPU only. We're making a file not a frame. Lucky we don't have to put A Quadro 4 in every box in a render farm.
Ars Technica Said it best:
"Dear Steve, more bogomips. Love, Johnny. Posted 7/20/2002 - 9:21PM, by johnnyace
The guys over at Digital Video Editing have taken the "what should I buy, PC or Mac" argument to its "logical" *cough* conclusion: Benchmarks. In their Benchmark Duel: Mac vs. PC, Round II, they've taken three machines, a Dell Precision 340 ( Single P4 2.53Ghz), an Apple PowerMac G4 dual 1Ghz, and a BOXX dual Athlon 2000+MP, and ran them head to head. 'Tis a shootout of high end prebuilt boxen with one goal in mind: "Which one is fastest?" In some tests, the results are negligible. In a photoshop benchmark, the dual G4 takes two seconds while the x86 machines take 1. Statistics say that I should care, but when I'm working hard, one or two seconds probably won't be a big deal. However, in the digital video tests, the Apple machine gets spanked! In render intensive tests, the G4 weighs in at 11:57, and the Athlon machine flies by at 7:11. I didn't care that the G4 box took an extra second on a photoshop render, but four minutes is a little more difficult to ignore.
With the prosumer interest in digital video production ramping up, many people are buying Apple hardware for the convenience of iMovie and assured compatibility with Apple branded DVD-R drives. But, articles such as this aren't going to help. And to be honest, as an ex-Mac poweruser I find the entire situation to be incredibly frustrating. From a hardware enthusiast's historical point of view, Apple had some of the best pre-built systems to be had for any price, when considering hardware alone. PPC processors with SCSI disk systems were, in theory, going to kick the crap out of your standard PC, and in many ways, they were superior technologies that appealed to a number of people.
Yet at this very same time, this killer hardware was trapped under an OS that couldn't keep up with the times. I'm sure some will disagree vehemently, but OS 9.2 and its predecessors, especially pre-8.5 systems, were the fences that kept impressive technology caged in a 10x10 foot back yard.
And what do we have today? The reverse! Except among those who are reticent to adapt, the MacOS of yester-century is nothing more than a bad memory. OS X rectifies almost all of the problems I ever had with the earlier OS, but now that the OS is up to date, the hardware is woefully out of date. So Apple, what gives? Does Steve Jobs' brain run on OS 8? I've seen good hardware, and good software; can you please try to do both of these things at the same time? If you do, I might even switch back."
You certainly will. Sledghammer is expected to suck power like a cat in an exaust pipe. It is also expected to have more flop/s/watt than anything yet.
I'll be happy to pump 1000 watts into the Sledghammer server that replaces four 500 watt servers.
"what you really mean is that two independant processes will each run as if on a dedicated processor (which they will). But multithreading will still have some memory and bus contention."
18 ns of latency to pull data from another mrocessor's memory.
6 ns latency to pull from processors memory.
6.4 Gb/s bandwidth.
Memory bandwidth is cumulative with processor count. for instance, 8 processors would have 51 Gb/s composite memory bandwidth.
A dual 1Ghz Mac can emulate x86 and performs as well as a 266Mhz PII
A 667 mhz 64 bit Alpha can emulate x86 but is only as fast as a 200mhz Pentium Pro
An 800 Mhz Itanic emulates x86 as fast as a 166Mhz Pentium.
Linux can emulate a cluster on a single machine.
Any PC with two network cards can emulate a Cisco router.
Intel stopped marketing Itanium's x86 emulation mode because it is abysmally slow. The emulator is of course compiled on Itanium's still very immature compilers so it will improve in the future.
The Sledgehammer contains a complete x86 core and a complete 64 bit risc core. At 800mhz it outperforms a 1.6Ghz Pentium 4 running stock Windows XP and stock applications.
Running 64 bit SUSE, the Sledghammer performs as well as an Itanium at the same clock speed.
Sledgehammer is expected to ship at 2.0 Ghz. It's should perform as fast as a pentium 4 at 3.4 Ghz. Each processor has it's own memory controller so there is no shared memory bottleneck for multiprocessing. 2 processors should be exactly twice as fast using multithreaded applications. Sledghammer scales to 8 processors.
Slashdot Mirror
Gee I dont know, at my one job we still have some 9500's and a 7100 with a 266Mhz G3 upgrade, these have been running 8 hours a day all week since like 1996. I still have my PowerCenter 132 with a 500Mhz G3, it runs fine. I could try and run OS X on these, but why bother?
Don't even start on upgrade path. You paid 300 bucks for a 266 mhz sonnet card when you could have paid 200 bucks for a Ghz+ processor and motherboard. You ain't going to make it far on a 266mhz G3 on a 50mhz bus.
For $3500 new mac prices, you can buy a complete new system every 9 months for 5 years.
Macs HAD good hardware. Apple stopped funding hardware upgrades when they started on OS X. Now they have a great OS and crap hardware.
It's not your fault. They are just significantly behind. OS X is not "slow". the fucking hardware is.
Wei Zhongxian, notorious eunuchs, no balls for life.
10 inch diameter 25 pound carbon fiber flywheel at 36,000 rpm.
.50 cal sniper rifle = 16,539 Joules
Edge speed is 1071 Miles per hour.
A "flander" is a large splinter that explodes off the inside of a ship's hull when a cannon ball hits broadside at sub-sonic velocities. Thus the term "smash to flanders".
a 25 pound cannonball will completely breach 8 inches of wood creating a manticore of wood splinter shrapnel.
A tornado will drive pieces of straw through a wall at subsonic speeds.
A winch cable will crack at supersonic speeds if it snaps. A winch cable will shear an engine block.
100 lashes is a death penalty.
Kinetic Energy = 1/2*I*w*w
I = moment of inertia --> ability of an object to resist changes in its rotational velocity
w = rotational velocity (rpm)
I = k *M*R*R (M=mass; R=Radius); k = intertial constant (depends on shape)
Inertial constants for different shapes:
Wheel loaded at rim (bicycle tire): k =1
solid disk of uniform thickness; k = 1/2
I assumed 4/5 because of the design they used
Kinetic Energy of flywheel = 68,428,800 Joules
357 Magnum = 937 Joules
4000 sniper rifle bullets worth of energy exploding outward in the form of tiny splinters of a substance that happens to have one of the highest tensile strengths. Assume 98% of the kinetic energy is lost to heat. 80 sniper bullets.
Bad news.
"Every time I've done this comparison, the Mac was about %10 cheaper, and usually still had extra stuff."
m
0 C: maccentral.macworld.com/news/0102/26.carmack.shtml +carmack+mac+pc+slashdot&hl=en&ie=UTF-8
Compare again.
You took the sucker's position. cut-n-paste:
http://www.heise.de/ct/english/02/05/182/
http://www.digitalvideoediting.com
"Benchmark Duel: Mac vs. PC, Round II"
http://www.teamlambchop.com/bench/303results.ht
(the dual G4 1Ghz is in 207th place @ 7 hrs 7 minutes, right behind the dual 933mhz PIII which is 3 minutes faster. Top place is held by an Athlon @ 2 hrs 48 minutes.)
http://216.239.51.100/search?q=cache:Eob9RvdJLC
I ask you: Did you really do any research at all?
If the 733 G4 is not as fast as the 1Ghz PIII, as Carmack stated, how do you expect the Dual G4 1Ghz to compete with a dual 1733 Athlon or Dual 2.2 Ghz Xeon?
The Mac can't even use a professional graphics card like the Quadro 900XGL or 3D Labs Wildcat III 6210. No usb 2.0. PCI bus limited to 180 MB/s. No DDR memory in their workstations. 133fsb G4 can't take advantage of DDR anyway. Insane priced monitors using old flat panel technology. Is lack of hardware support a "feature"?
Open your EYES because the only "extra stuff" in a mac is price!
No, my posts are not always popular. I'm a Mac user, remember.
r am eletter.cgi?%2F2002%2F05_may%2Ffeatures%2Fcw_aesho wdown.htm
r am eletter.cgi?%2F2002%2F05_may%2Ffeatures%2Fcw_aesho wdown.htm
m
Feeling like martyring yourself on the mac sword? Do you use them just because you percieve them to be unpopular?
"Well, since their hardware already outperforms (MTBF, useable life, ROI) nearly all x86 hardware out there, I'd say they have a good head start.
"Informed dialog? I'm ready when you are"
No, you are not ready. You took the sucker's position. cut-n-paste:
http://www.heise.de/ct/english/02/05/182/
http://www.digitalvideoediting.com/cgi-bin/getf
http://www.digitalvideoediting.com/cgi-bin/getf
http://www.teamlambchop.com/bench/303results.ht
(the dual G4 1Ghz is in 207th place @ 7 hrs 7 minutes, right behind the dual 933mhz PIII which is 3 minutes faster. Top place is held by an Athlon @ 2 hrs 48 minutes.)
Return on Investment: Paying SEVEN TIMES AS MUCH for a computer that is HALF AS FAST
Usable life: what is the usable life on a computer that is 2 years obsolete when you purchase it? Where did the "5 year mac" go?
Mean time between failure: based purely on OS X's upgrade cycle and time to install upgrades give you 99.8% reliability. But the spinning beach ball of death adds another few hour a year down. 99.6%. Then the CD won't eject and is now missing the paperclip hole. 99.5%. Then the printer stops responding, reboot again 99.4%. This app needs 9.2 to run, classic is no go 99.1% Cracked hinges on case 1 week down 97%.
Not exactly 5 nines. Not even 2 nines. In fact, that is a 9 and a 7.
MTBF is less than 2 weeks. Better than win98. Not as good as straight FreeBSD. About the same as Win2K. Wonderful. Just as reliable as an OS with 64,000 bugs.
These forums are not about gaining karma. These forums are about speaking the truth, opening an informed dialogue and not shying away from contentious issues.
Obviously, your only intent is to preserve your precious karma. You only say what you know will be popular. The consummate politician. Your posts are popular but are filled with nothing but populist drivel. You have never taken a stand for anything you believe in. You only parrot the party line.
Spineless.
Whoa, dude! My Karma is, like, "Excellent"!
We don't care.
This is a discussion, not a popularity contest.
Karma does not get you elected.
Your focus on karma at the expense of the discussion is sad.
You own a Mac.
I own 180 Macs.
Their cost is non-trivial.
Their performance is substandard.
Their OS is the best on the market.
You are likely to be content with your mac's performance.
I could care less.
Apple will not get another dime from me untill their harware is held to the standard their OS is.
Even Steve Jobs prefers the performance of x86 over PowerPC. Pixar uses x86 linux clusters.
Shut the Fuck up.
Generic hardware at speed x is $500.
Apple hardware at speed x is $2000.
SO, apple users have already paid $1500 just to use OS X.
-or-
Apple users have paid $1371 for a shiny case if OS X only costs $129.
For that price the case better be easy and cook breakfast in the morning.
Pay the full price to Apple directly. They have a great OS and really really need the money for their hardware development team.
Apple has to get the money to convert to Sledgehammer/Nvidia from somewhere.
I thought of this years ago. Then realized I was wrong. How much power does your local AM radio station put out? 50,000 watts. Will the ammount of power required to broadcast to three states ever drop? Nope. How many 50,000 watt radio stations are there in the US alone? Over 8000.
Will XM sattelite radio change that? Has linux been able to break Microsoft's monopoly?
user interface just got a lot easier than:
,./
qwe iop
asd kl;
zxc
oooh ahhhh pretty.
Really needs a good flight model. Stopping to turn is annoying. Foward and reverse need keys with mouse look, reverse x,y axis. Would also be nice to be able to select pairs of stars and get distance data between them. Constellations would be nice too... sort of a stargate style. A "what does orion look like from polaris" sort of thing.
Some people win the lottery.
Some people buy 6 substandard drives from the same manufacturer.
Some people use a 5400rpm CPU fan and 5400 rpm drives and expect they won't set up narrows bridge style resonate frequencies in their cases.
Some people do not properly cool their cases.
Some people bang their boxes around at once a month lan parties and wonder why their drives fail.
Some people overclock their machines but don't use western digital drives because they tend to behave badly.
So the Athlon MP was at the same disadvantage... Two processors with one sitting idle.
unwilling to be "tracked"
...
Like on the subway "train"
or Bart "train"
or euro-"rail"
You meant that as a pun didn't you?
Yeah, keep all the paranoid freaks away from me. Make the lowly cattle use mass transit like "planes" or "cruise ships" or "elevators".
I'll be driving accross the Pacific.
Oh, that's just a little one.
We'll just tag it and throw it back.
Good thing we have a catch-n-release program in place.
"My computer's longest uptime is 12 hours. I've tried windows, redhat and mandrake. Windows has performed the best."
That's a terrible reflection on you.. and BTW, your webserver is down also.
So what you are really saying is OS X can't walk and chew gum at the same time... No, OS X has no trouble prioritizing background tasks. Running a distributed net client would not affect it in the slightest. Since a single Mac could never hope to host a tier 1 pr0n site, I'm going to assume that was a joke.
Video card has no bearing on render time. Rendering is done by the CPU only. We're making a file not a frame. Lucky we don't have to put A Quadro 4 in every box in a render farm.
Ars Technica Said it best:
"Dear Steve, more bogomips. Love, Johnny.
Posted 7/20/2002 - 9:21PM, by johnnyace
The guys over at Digital Video Editing have taken the "what should I buy, PC or Mac" argument to its "logical" *cough* conclusion: Benchmarks. In their Benchmark Duel: Mac vs. PC, Round II, they've taken three machines, a Dell Precision 340 ( Single P4 2.53Ghz), an Apple PowerMac G4 dual 1Ghz, and a BOXX dual Athlon 2000+MP, and ran them head to head. 'Tis a shootout of high end prebuilt boxen with one goal in mind: "Which one is fastest?" In some tests, the results are negligible. In a photoshop benchmark, the dual G4 takes two seconds while the x86 machines take 1. Statistics say that I should care, but when I'm working hard, one or two seconds probably won't be a big deal. However, in the digital video tests, the Apple machine gets spanked! In render intensive tests, the G4 weighs in at 11:57, and the Athlon machine flies by at 7:11. I didn't care that the G4 box took an extra second on a photoshop render, but four minutes is a little more difficult to ignore.
With the prosumer interest in digital video production ramping up, many people are buying Apple hardware for the convenience of iMovie and assured compatibility with Apple branded DVD-R drives. But, articles such as this aren't going to help. And to be honest, as an ex-Mac poweruser I find the entire situation to be incredibly frustrating. From a hardware enthusiast's historical point of view, Apple had some of the best pre-built systems to be had for any price, when considering hardware alone. PPC processors with SCSI disk systems were, in theory, going to kick the crap out of your standard PC, and in many ways, they were superior technologies that appealed to a number of people.
Yet at this very same time, this killer hardware was trapped under an OS that couldn't keep up with the times. I'm sure some will disagree vehemently, but OS 9.2 and its predecessors, especially pre-8.5 systems, were the fences that kept impressive technology caged in a 10x10 foot back yard.
And what do we have today? The reverse! Except among those who are reticent to adapt, the MacOS of yester-century is nothing more than a bad memory. OS X rectifies almost all of the problems I ever had with the earlier OS, but now that the OS is up to date, the hardware is woefully out of date. So Apple, what gives? Does Steve Jobs' brain run on OS 8? I've seen good hardware, and good software; can you please try to do both of these things at the same time? If you do, I might even switch back."
You certainly will. Sledghammer is expected to suck power like a cat in an exaust pipe. It is also expected to have more flop/s/watt than anything yet.
I'll be happy to pump 1000 watts into the Sledghammer server that replaces four 500 watt servers.
Renders take twice as long so it should cost half as much.
more like on par with $10,000 6 megapixel cameras. Have you priced them and their proprietary lens sets lately?
"what you really mean is that two independant processes will each run as if on a dedicated processor (which they will). But multithreading will still have some memory and bus contention."
18 ns of latency to pull data from another mrocessor's memory.
6 ns latency to pull from processors memory.
6.4 Gb/s bandwidth.
Memory bandwidth is cumulative with processor count. for instance, 8 processors would have 51 Gb/s composite memory bandwidth.
Anyone with anything intelligent to add to this discussion is either busy patching or cracking
NOT posting
Plenty of 12 volt power.
Lots of fan noise in the trunk is OK.
The new shuttles have beautiful copper heat pipes that are begging for monster automotive airflow.
Think BIG. 9 inch diameter 600 cfm should be fine
Do NOT forget a filter. Try a Hepa home air conditioning filter.
Do not recirculate the already hot air in your trunk. Use NACA ducts
A dual 1Ghz Mac can emulate x86 and performs as well as a 266Mhz PII
A 667 mhz 64 bit Alpha can emulate x86 but is only as fast as a 200mhz Pentium Pro
An 800 Mhz Itanic emulates x86 as fast as a 166Mhz Pentium.
Linux can emulate a cluster on a single machine.
Any PC with two network cards can emulate a Cisco router.
Intel stopped marketing Itanium's x86 emulation mode because it is abysmally slow. The emulator is of course compiled on Itanium's still very immature compilers so it will improve in the future.
The Sledgehammer contains a complete x86 core and a complete 64 bit risc core. At 800mhz it outperforms a 1.6Ghz Pentium 4 running stock Windows XP and stock applications.
Running 64 bit SUSE, the Sledghammer performs as well as an Itanium at the same clock speed.
Sledgehammer is expected to ship at 2.0 Ghz. It's should perform as fast as a pentium 4 at 3.4 Ghz. Each processor has it's own memory controller so there is no shared memory bottleneck for multiprocessing. 2 processors should be exactly twice as fast using multithreaded applications. Sledghammer scales to 8 processors.
Microsoft Acronyms:
r y. asp
_ ab brev.html
http://www.microsoft.com/hwdev/resources/glossa
Government and Military acronyms:
http://www.ulib.iupui.edu/subjectareas/gov/docs
And the Winner is:
Not us.
"A common integrated processor (CIP), a central "brain" with the equivalent computing throughput of two Cray supercomputers"
2 95 003.pdf
Um.. No:
ftp://download.intel.com/design/i960/perform/27
(Intel's i860 performance brief)