Bitcoin Forum
March 28, 2024, 08:57:53 PM *
News: Latest Bitcoin Core release: 26.0 [Torrent]
 
   Home   Help Search Login Register More  
Pages: [1]
  Print  
Author Topic: How many FLOP/s is there in a gigahash?  (Read 25311 times)
mackminer (OP)
Sr. Member
****
Offline Offline

Activity: 348
Merit: 251



View Profile
November 19, 2011, 03:18:55 PM
 #1

In fact, what does gigahash mean exactly?

Also without getting into much technical detail can anyone explain what it means when you say you are generating a hash?

Thanks.

1BFf3Whvj118A5akc5fHhfLLwxYduMmq1d
1711659473
Hero Member
*
Offline Offline

Posts: 1711659473

View Profile Personal Message (Offline)

Ignore
1711659473
Reply with quote  #2

1711659473
Report to moderator
"Bitcoin: mining our own business since 2009" -- Pieter Wuille
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction.
1711659473
Hero Member
*
Offline Offline

Posts: 1711659473

View Profile Personal Message (Offline)

Ignore
1711659473
Reply with quote  #2

1711659473
Report to moderator
1711659473
Hero Member
*
Offline Offline

Posts: 1711659473

View Profile Personal Message (Offline)

Ignore
1711659473
Reply with quote  #2

1711659473
Report to moderator
DeathAndTaxes
Donator
Legendary
*
Offline Offline

Activity: 1218
Merit: 1063


Gerald Davis


View Profile
November 19, 2011, 03:22:59 PM
Last edit: December 20, 2011, 07:23:36 PM by DeathAndTaxes
 #2

A "hash" is actually 2 SHA-256 hashing operations so.

Bitcoin hash = SHA-256(SHA-256(blockheader including nonce)

A Gigahash = 1 billion hashes.

To perform one bitcoin hash on an AMD GPU takes about 3500 ALU operations.

There is no direct conversion between FLOPS (floating point operations per second) and hashes because hashes involve integer operations (whole number math) and FLOPS involving obviously floating point math.  Any claim of Bticoin is x flops is simply an aproximation of the potential floating point power as the Btitcoin network uses 0.00 FLOPS.

Various sites come up with an estimate by on the number of FLOPS per hash by looking at how "fast" average hardware is on each.

Example:
AMD 5870 5970(stock clocks)
~ 700MH/s
~ 2700 GLOPS (single precision)
~ 5340 GFLOPS (double precision)

http://en.wikipedia.org/wiki/Comparison_of_AMD_graphics_processing_units#PCIe_.28HD_5xxx.29

Using that you can get an estimated relationship between hashes and flops and then use networks hashing rate to estimate network's potential in TFLOPS.
ngzhang
Hero Member
*****
Offline Offline

Activity: 592
Merit: 501


We will stand and fight.


View Profile
November 19, 2011, 05:39:14 PM
 #3

approx.1300 32bit add operaions.
finway
Hero Member
*****
Offline Offline

Activity: 714
Merit: 500


View Profile
November 19, 2011, 05:42:35 PM
 #4

According to bitcoinwatch.com

1 Hash = 12,697 FLOPs

gmaxwell
Moderator
Legendary
*
Offline Offline

Activity: 4158
Merit: 8343



View Profile WWW
November 19, 2011, 06:26:11 PM
 #5

According to bitcoinwatch.com
1 Hash = 12,697 FLOPs

Thats a gibberish number. It is like saying that one mile per hour is equal to 14.285 pounds (because some car that weighs 2000 lbs can go 140 MPH).

There are no floating point operations involved in the calculation of a bitcoin hash. None at all. 0 FLOPS.

Ngzhang says above that there are about 1300 32-bit operations (in one bitcoin hash) which sounds about right. So one 1GH/s would be equal to 1,300,000,000,000 operations per second.

If you're looking to, e.g. compare bitcoin's speed with various supercomputers you can just figure out how fast the supercomputer could mine.  For example, one of the top machines is the Jaguar supercomputer which uses fairly standard opteron cores. I think my fairly boring rough numbers put it at about 522 GH/s.  (pshaw, who says CPU mining is useless? Wink )
DiabloD3
Legendary
*
Offline Offline

Activity: 1162
Merit: 1000


DiabloMiner author


View Profile WWW
December 02, 2011, 04:36:29 AM
 #6

According to bitcoinwatch.com
1 Hash = 12,697 FLOPs

Thats a gibberish number. It is like saying that one mile per hour is equal to 14.285 pounds (because some car that weighs 2000 lbs can go 140 MPH).

There are no floating point operations involved in the calculation of a bitcoin hash. None at all. 0 FLOPS.

Ngzhang says above that there are about 1300 32-bit operations (in one bitcoin hash) which sounds about right. So one 1GH/s would be equal to 1,300,000,000,000 operations per second.

If you're looking to, e.g. compare bitcoin's speed with various supercomputers you can just figure out how fast the supercomputer could mine.  For example, one of the top machines is the Jaguar supercomputer which uses fairly standard opteron cores. I think my fairly boring rough numbers put it at about 522 GH/s.  (pshaw, who says CPU mining is useless? Wink )


I agree. Not only that, FLOPs aren't all made equal. A lot of people have done stuff like specifically state P4 flops, which has a strict conversion factor comparing something along the lines of P4s doing SSE MADs to the same instruction in integer math, etc etc etc.

I like my computational power metric better: number of 5850s at stock speed.

ElectricMucus
Legendary
*
Offline Offline

Activity: 1666
Merit: 1057


Marketing manager - GO MP


View Profile WWW
December 02, 2011, 05:12:17 AM
 #7

For integer operations there is the figure of MIPS and GIPS or GOPs, as for integer instructions.
Floating point performance is only related to the clock speed not integer performance.
finway
Hero Member
*****
Offline Offline

Activity: 714
Merit: 500


View Profile
December 02, 2011, 06:54:47 AM
 #8

For example, one of the top machines is the Jaguar supercomputer which uses fairly standard opteron cores. I think my fairly boring rough numbers put it at about 522 GH/s.

So, how much FLOPs/s is it ?

Matthew N. Wright
Untrustworthy
Hero Member
*****
Offline Offline

Activity: 588
Merit: 500


Hero VIP ultra official trusted super staff puppet


View Profile
December 02, 2011, 07:00:20 AM
 #9

I'm curious, how many giggadicks are in a dickaflop and how many pedophiles are in a pedoflop too?

Jonathan Ryan Owens
Donator
Sr. Member
*
Offline Offline

Activity: 392
Merit: 252



View Profile WWW
December 03, 2011, 09:35:21 AM
 #10

I'm curious, how many giggadicks are in a dickaflop and how many pedophiles are in a pedoflop too?

I can't find any information on #2, but I did find this:

(1) http://pastebin.com/RQe0S9Pi

Matthew N. Wright
Untrustworthy
Hero Member
*****
Offline Offline

Activity: 588
Merit: 500


Hero VIP ultra official trusted super staff puppet


View Profile
December 15, 2011, 06:01:48 AM
 #11

I'm curious, how many giggadicks are in a dickaflop and how many pedophiles are in a pedoflop too?

I can't find any information on #2, but I did find this:

(1) http://pastebin.com/RQe0S9Pi

That is a very reputable source.

BinaryMage
Hero Member
*****
Offline Offline

Activity: 560
Merit: 500


Ad astra.


View Profile
December 20, 2011, 01:49:29 AM
Last edit: December 20, 2011, 04:55:05 PM by BinaryMage
 #12

A "hash" is actually 2 SHA-256 hashing operations so.

Bitcoin hash = SHA-256(SHA-256(blockheader including nonce)

A Gigahash = 1 billion hashes.

To perform one bitcoin hash on an AMD GPU takes about 3500 ALU operations.

There is no direct conversion between FLOPS (floating point operations per second) and hashes because hashes involve integer operations (whole number math) and FLOPS involving obviously floating point math.  Any claim of Bticoin is x flops is simply an aproximation of the potential floating point power as the Btitcoin network uses 0.00 FLOPS.

Various sites come up with an estimate by on the number of FLOPS per hash by looking at how "fast" average hardware is on each.

Example:
AMD 5870 (stock clocks)
~ 700MH/s
~ 2700 GLOPS (single precision)
~ 5340 GFLOPS (double precision)

http://en.wikipedia.org/wiki/Comparison_of_AMD_graphics_processing_units#PCIe_.28HD_5xxx.29

Using that you can get an estimated relationship between hashes and flops and then use networks hashing rate to estimate network's potential in TFLOPS.


A HD 5870 puts out ~380 MH/s with stock clocks, not ~700. Where did you get that number from?

Yes, you can get a relationship, though it varies card-to-card. My suggestion would be to find the relationships for the 5870, 5850, and 5830, as I suspect those are the most common mining cards, though I could be wrong, and average those together. Then you can use the network hash rate to find the approximate FLOPS as stated above.

-- BinaryMage -- | OTC | PGP
DeathAndTaxes
Donator
Legendary
*
Offline Offline

Activity: 1218
Merit: 1063


Gerald Davis


View Profile
December 20, 2011, 07:23:17 PM
 #13

A HD 5870 puts out ~380 MH/s with stock clocks, not ~700. Where did you get that number from?

Typo brain said 5970 keyboard said 5870.
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!