Badly optimized Mac PPC app?

Martin P.
Martin P.
Joined: 17 Feb 05
Posts: 162
Credit: 40,156,217
RAC: 99
Topic 193190

Check this computer: http://einsteinathome.org/host/18591/tasks

While the S5R2-app took appr. 93,000 seconds for 665 credits (=25,7 credits/hour), the new S5R3-app takes 48,000 seconds for only 220 credits (=16,4 credits/hour). This is a loss of more than 30%!!!!!

Either the Mac-PPC-app is extremely badly optimized or there is something wrong with the credit allocation.

Since we do not see a major hit in the overall daily credits there must be something wrong with the Mac-app.

This is particularly bad news because the PPC-app traditionally was one of the best applications that made full use of the PPC's Altivec unit.

Bikeman (Heinz-Bernd Eggenstein)
Bikeman (Heinz-...
Moderator
Joined: 28 Aug 06
Posts: 3,516
Credit: 455,959,483
RAC: 46,276

Badly optimized Mac PPC app?

Currently it looks like all apps compiled with the GCC compiler (Linux x86, MacOS x86, Mac OS PPC) take a credit/hours hit compared to S5R2, whereas the Windows app (compiled with MS Visual C/C++) has about the same credits/hour ratio on most (not all) hosts. As most (about 85%) of the hosts are running under Windows, the overall effect on credits/day is barely visible.

CU
BRM

peanut
peanut
Joined: 4 May 07
Posts: 162
Credit: 9,644,812
RAC: 0

Having a Mac does have some

Having a Mac does have some draw backs that rear their ugly head sometimes.

No one should blame a project for concentrating on the biggest part of their users first.

I just did a man gcc on my Mac and looked at all the options. Holy cow there are a bunch of them. And each one may act differently on different processors/OS'es. It is really quite amazing that BOINC runs as well as it does on so many different platforms.

Bikeman (Heinz-Bernd Eggenstein)
Bikeman (Heinz-...
Moderator
Joined: 28 Aug 06
Posts: 3,516
Credit: 455,959,483
RAC: 46,276

RE: Having a Mac does have

Message 73628 in response to message 73627

Quote:

Having a Mac does have some draw backs that rear their ugly head sometimes.

No one should blame a project for concentrating on the biggest part of their users first.

I think in S5R2 it was quite the opposite, (the Macs were a bit faster than comparable Windows PCs), not to forget the initial AMD-on-Windows performance problem of R5R2. I'm sure this will be addressed during S5R3. Stay tuned.

Hopefully there will be hand-crafted assemply code routines for all hot-spots and the compiler specific differences will be reduced.

CU
H-BE

peanut
peanut
Joined: 4 May 07
Posts: 162
Credit: 9,644,812
RAC: 0

RE: I think in S5R2 it was

Message 73629 in response to message 73628

Quote:
I think in S5R2 it was quite the opposite, (the Macs were a bit faster than comparable Windows PCs)

Just like the stock market, you have your ups and downs. Just have to look long term :)

Odysseus
Odysseus
Joined: 17 Dec 05
Posts: 372
Credit: 10,721,794
RAC: 4,024

For the past couple of months

For the past couple of months my dual G5’s RAC for E@h has remained comparable to that for SETI@home, where I run an optimized app. Admittedly the latter project hasn’t been able to supply all the work requested recently, but it may be worth noting that both are returning considerably more credit than the other projects this host runs with an equal resource share—about double, in fact.

[AF>Le_Pommier>Macbidouille.com]CRISTOBOOL
[AF>Le_Pommi...
Joined: 10 Dec 05
Posts: 59
Credit: 62,971
RAC: 0

Hello i have a problem

Hello i have a problem einstein@home doesn't work since the S5R3 update !!

i remove the app and the xml info ; but einstein failed to download the S5R3 app for darwin-PPC :

Lun 1 oct 19:46:11 2007||[error] No URL for file transfer of einstein_S5R2_4.34_powerpc-apple-darwin
Lun 1 oct 19:46:11 2007|Einstein@Home|[error] Can't initialize file transfer for einstein_S5R2_4.34_powerpc-apple-darwin
Lun 1 oct 19:46:11 2007||Processor: 1 Power Macintosh Power Macintosh [Power Macintosh Model PowerMac7,2] [AltiVec]
Lun 1 oct 19:46:11 2007||Memory: 1.50 GB physical, 237.89 GB virtual
Lun 1 oct 19:46:11 2007||Disk: 297.97 GB total, 237.65 GB free
Lun 1 oct 19:46:11 2007|Einstein@Home|URL: http://einstein.phys.uwm.edu/; Computer ID: 721621; location: home; project prefs: default

And it appear that einstein try to download a S5R2 app ????

Bernd Machenschalk
Bernd Machenschalk
Moderator
Administrator
Joined: 15 Oct 04
Posts: 3,938
Credit: 200,188,661
RAC: 43,606

RE: Hello i have a problem

Message 73632 in response to message 73631

Quote:

Hello i have a problem einstein@home doesn't work since the S5R3 update !!

i remove the app and the xml info ; but einstein failed to download the S5R3 app for darwin-PPC :

Lun 1 oct 19:46:11 2007||[error] No URL for file transfer of einstein_S5R2_4.34_powerpc-apple-darwin
Lun 1 oct 19:46:11 2007|Einstein@Home|[error] Can't initialize file transfer for einstein_S5R2_4.34_powerpc-apple-darwin
Lun 1 oct 19:46:11 2007||Processor: 1 Power Macintosh Power Macintosh [Power Macintosh Model PowerMac7,2] [AltiVec]
Lun 1 oct 19:46:11 2007||Memory: 1.50 GB physical, 237.89 GB virtual
Lun 1 oct 19:46:11 2007||Disk: 297.97 GB total, 237.65 GB free
Lun 1 oct 19:46:11 2007|Einstein@Home|URL: http://einstein.phys.uwm.edu/; Computer ID: 721621; location: home; project prefs: default

And it appear that einstein try to download a S5R2 app ????

Uh. I see the problem. Try resetting the project.

BM

BM

[AF>Le_Pommier>Macbidouille.com]CRISTOBOOL
[AF>Le_Pommi...
Joined: 10 Dec 05
Posts: 59
Credit: 62,971
RAC: 0

thanks it seems to be working

thanks it seems to be working now !

Martin P.
Martin P.
Joined: 17 Feb 05
Posts: 162
Credit: 40,156,217
RAC: 99

RE: Check this computer:

Quote:

Check this computer: http://einsteinathome.org/host/18591/tasks

While the S5R2-app took appr. 93,000 seconds for 665 credits (=25,7 credits/hour), the new S5R3-app takes 48,000 seconds for only 220 credits (=16,4 credits/hour). This is a loss of more than 30%!!!!!

Either the Mac-PPC-app is extremely badly optimized or there is something wrong with the credit allocation.

Since we do not see a major hit in the overall daily credits there must be something wrong with the Mac-app.

This is particularly bad news because the PPC-app traditionally was one of the best applications that made full use of the PPC's Altivec unit.

Still waiting for an improvement. Anyone working on this?

DanNeely
DanNeely
Joined: 4 Sep 05
Posts: 1,313
Credit: 1,727,809,831
RAC: 956,352

Significant app optimization

Significant app optimization is on hold while the team trys to find the last handful of low occurence bugs.

A linux x86 beta app was recently put out using a different version of gcc that produced faster code. The mac apps are also compiled using gcc, I'd assume at some point a test will be done to see if the mac version also benefits.

The historic edge mac had in the first half of s4 was because the inner loop of the PPC app was hand coded assembly while the x86 apps weren't. The apps used in s5r1 were all equally tweaked and had similar performance levels. The current s5r3 apps all are purely compiled code.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.