3% faster mining with phoenix+phatk for everyone

[mrb]

I was wondering when the community would discover this optimization... nice one bitless :-)

For the record, hdminer has implemented this maj() optimization since day 1:

Code:

        # ibit_extract patched to BFI_INT at runtime
        $code .=
        "    ixor $tmp0, $a, $b\n".
        "    ibit_extract $tmp0, $a, $c, $tmp0\n";

Phoenix is probably very close to hdminer's performance now, on HD 69xx.

[Wildvest]

from 402 -> 415 thanks

[Bert]

Sapphire 5870 @ 1000/347 before 442.7 Mhash/sec after 452.1 Mhash/sec overall an increase of 2.1%

[themike5000]

I'm still looking at the same rejection statistics after 1100 shares.  Thanks!

[sanchaz]

5850 890/300: 345 -» 355
5850 825/300: 318 -» 325
5850 900/300: 344 -» 355

donation on its way thx.

[KiLeRrosS]

Thank you

5830 - 314 -> 324 (1025/300)
5830 - 308 -> 316 (1000/300)
5850 - 370 -> 379 (930/300)

I've 57MHps more - almost 3%

I sent small donations.

[AtlasONo]

FYI, You can make the identical change to phoenix+poclbm with the same 2% increase in speed.

Do tell, If theres a simple file to replace that you can upload i'll definitly Tip you
Winx86 GUIminer-poclbm

http://www.mediafire.com/?jth8eicn9iifnlf

Extract contents to the location of your guiminer folder and allow them to replace the existing files.

[Rob P.]

Just tossing my confirmations out there:
...
So, the increase appears to also cause additional rejects that should be discounted from total increase gain, cutting it down a full 1% in my case.

This is really not good. I honestly do not know why this would happen; are you sure it is related to the patch and isn't a result in the general randomness when searching for solutions? Perhaps someone else, more familiar with bitcoin mining than me, can chime in?

Not saying it's the patch, just reporting the results.  That's why I posted the population of shares each measurement was done over.

If my reject rates are higher over a prolonged period, then I may change one of my cards running on the same rig, back to the old kernel values and compare them head to head over a few days.

[Freakin]

412 to 423 on my 5870
290 to 302 on my 5830s

[bitless]

I was wondering when the community would discover this optimization... nice one bitless :-)

For the record, hdminer has implemented this maj() optimization since day 1:

Code:

        # ibit_extract patched to BFI_INT at runtime
        $code .=
        "    ixor $tmp0, $a, $b\n".
        "    ibit_extract $tmp0, $a, $c, $tmp0\n";

Phoenix is probably very close to hdminer's performance now, on HD 69xx.

Dude, awesome  so this accounts for 3% out of your 6.4% improvement, where are the other 3.4% coming from? I don't have 250 btc, in fact I only have ~2 that have been donated to me so far. (Please note - if you decide to share this, post it,don't pm me )

[c_k]

A small donation coming your way for the excellent work

Many thanks!

[PcChip]

I was wondering when the community would discover this optimization... nice one bitless :-)

Makes me wonder how many other private modifications are in use right now

[bitless]

I was wondering when the community would discover this optimization... nice one bitless :-)

Makes me wonder how many other private modifications are in use right now

Also makes me wonder why people don't post them for everyone to see. So, 3% or even 5% speed increase doesn't really matter all that much if you're just a regular guy with a couple of ATI cards, right? Or am I wrong?

PcChip - give me your best advice, should I keep my next optimization to myself or post it?

[PcChip]

Also makes me wonder why people don't post them for everyone to see. So, 3% or even 5% speed increase doesn't really matter all that much if you're just a regular guy with a couple of ATI cards, right? Or am I wrong?

PcChip - give me your best advice, should I keep my next optimization to myself or post it?

I can't answer that my friend, only you can.

If you're the type of person who loves tinkering with asm/opencl/hardeware code just for fun, and improving things for the community (which it seems like you are, and a redditor as well - highfive! [Did you go to a reddit meetup saturday?]) then it makes sense to continue posting them like you are.

If you're in bitcoin for profits, and want to use your intelligence to tweak the code to give yourself a (totally fair) advantage over the competition, then obviously it's not in your best interest to post it.  Note that I'm not saying there's anything wrong with this scenario, because I can't even say which route I'd pick myself.

I can say however, that I very much appreciated that speedup you posted, as did many others, and I hope you get many more BTC than the five you currently had donated to you at http://blockexplorer.com/address/15igh5HkCXwvvan4aiPYSYZwJZbHxGBYwB

[BombaUcigasa]

I can say however, that I very much appreciated that speedup you posted, as did many others, and I hope you get many more BTC than the five you currently had donated to you at http://blockexplorer.com/address/15igh5HkCXwvvan4aiPYSYZwJZbHxGBYwB

He actually had 1.4 BTC from other sources, but surely for such a small and important contribution he is rewarded decently.

This is one of those moments when you think... is it right to make over 60 bucks for 1 LOC? Is it right to make just a measly 60 bucks for giving EVERYONE 3% more money?

[PcChip]

This is one of those moments when you think... is it right to make over 60 bucks for 1 LOC? Is it right to make just a measly 60 bucks for giving EVERYONE 3% more money?

Do the math on how much extra income hundreds of people are getting, and then answer that.

Also, I didn't want to say anything at first since it could have been an anomaly, but I've now realized this on four separate cards - my GPU usage (and thus hashrate) has always fluctuated like a small sine wave from 99% - 90% , after this patch, they all stay a straight line 99% , so that's way more than a 3% increase in hashrate for me.

[coblee]

I agree Bitless deserves more donation. But the truth about mining is that if EVERYONE gets 3% improvement, the difficulty level will just go up by 3% and everyone ends up making the same. So that's why some people may be hiding their private optimizations so that only they alone benefit. Anyways, but I truly appreciate what Bitless has done. Hope you get more donations.

[BombaUcigasa]

my GPU usage (and thus hashrate) has always fluctuated like a small sine wave from 99% - 90% , after this patch, they all stay a straight line 99% , so that's way more than a 3% increase in hashrate for me.

What's weird, mine went from 90%-96% to 96% straight but the added performance adds 1.5C to the temperature, I might have to clock down a bit to get tot he previous 90C stable line, which means I am forfeiting the benefits of the above optimization. At least I use less energy, the Earth will thank us all...

[simplecoin]

Donation sent. not much, but hopefully we can get a bunch of little donations headed your way!

[bitless]

my GPU usage (and thus hashrate) has always fluctuated like a small sine wave from 99% - 90% , after this patch, they all stay a straight line 99% , so that's way more than a 3% increase in hashrate for me.

What's weird, mine went from 90%-96% to 96% straight but the added performance adds 1.5C to the temperature, I might have to clock down a bit to get tot he previous 90C stable line, which means I am forfeiting the benefits of the above optimization. At least I use less energy, the Earth will thank us all...

Same here, actually. I was ok with 6870 overclocked to 1000 MHz, but after the change it became unstable so I had to go down to 975, which is kinda sad. Yet, I blame it on poor ventilation in my case, so may be I'll get it running at 1000 again, eventually