Bitcoin Forum
December 05, 2016, 04:41:36 AM *
News: Latest stable version of Bitcoin Core: 0.13.1  [Torrent].
 
   Home   Help Search Donate Login Register  
Pages: [1]
  Print  
Author Topic: Network hash just spiked about 50%  (Read 2045 times)
cpt_howdy
Member
**
Offline Offline

Activity: 70



View Profile
February 18, 2012, 07:52:21 PM
 #1

Wow. Just after we come to the end of another 2016 block period, the hash rate ramps up massively to ~15Thash/s.

This says to me that (a) Miners were deliberately keeping their rigs in 2nd-gear until the difficulty rolled over (stayed constant at ~1380000) (b) They did this to maximise their profits (in BTC at least) during the next 2 weeks.

Why would they do this? Well, probably because they're predicting a big price crash, and are going to power down those rigs at the end of this 2 week period. And why not? If the hash rate stays like this for 2 weeks, come the end of this 2016 blocks, the price/difficulty ratio is going to be so low it will be unprofitable to mine for all but the most efficient. Wheat from the chaff...
1480912896
Hero Member
*
Offline Offline

Posts: 1480912896

View Profile Personal Message (Offline)

Ignore
1480912896
Reply with quote  #2

1480912896
Report to moderator
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction. Advertise here.
1480912896
Hero Member
*
Offline Offline

Posts: 1480912896

View Profile Personal Message (Offline)

Ignore
1480912896
Reply with quote  #2

1480912896
Report to moderator
RandyFolds
Sr. Member
****
Offline Offline

Activity: 434



View Profile
February 18, 2012, 08:04:27 PM
 #2

No, the global hashrate is extrapolated from the rate that blocks are found. A lucky streak will make it look like the hashrate is higher than it actually is.

Beyond that, the sample period is too small immediately following a difficulty change so the numbers are always way off for a few days.

▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
▓▓ ONEDICE.ME ▓▓▓▓▓ BEST DICE EXPERIENCE ▓▓▓▓ PLAY OR INVEST ▓▓▓▓▓▓
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
the joint
Legendary
*
Offline Offline

Activity: 1792



View Profile
February 18, 2012, 08:16:47 PM
 #3

No, the global hashrate is extrapolated from the rate that blocks are found. A lucky streak will make it look like the hashrate is higher than it actually is.

Beyond that, the sample period is too small immediately following a difficulty change so the numbers are always way off for a few days.

Looks to me that the "luck" we're seeing is more than simple variance.

Kluge
Donator
Legendary
*
Offline Offline

Activity: 1218


Michael, send me some coins before I hitman you


View Profile
February 18, 2012, 08:19:00 PM
 #4

If miners really quit mining after price drops (which I still don't think is nearly as strong a correlation as many've said), then I'd assume GPUMax's extremely generous PPS rate has attracted the additional miners.

Don't mix your coins someone said isn't legal
DeepBit
Donator
Hero Member
*
Offline Offline

Activity: 532


We have cookies


View Profile WWW
February 18, 2012, 08:39:10 PM
 #5

Deepbit's luck for last 24h is 20% better than expected, so I can believe that this spike is caused by luck.

Welcome to my bitcoin mining pool: https://deepbit.net ~ 3600 GH/s, Both payment schemes, instant payout, no invalid blocks !
Coming soon: ICBIT Trading platform
cpt_howdy
Member
**
Offline Offline

Activity: 70



View Profile
February 18, 2012, 09:03:14 PM
 #6

No, the global hashrate is extrapolated from the rate that blocks are found. A lucky streak will make it look like the hashrate is higher than it actually is.

Beyond that, the sample period is too small immediately following a difficulty change so the numbers are always way off for a few days.

I agree with you first point - it is true that it's block discovery rate, not hashrate, that is directly measured, and that it's possible we're just seeing a lucky period. However, your second point doesn't make any sense: what do you mean by the sample period? The block discovery rate is calculated by adding up N blocks over the past T minutes/hours, and then calculating N/T. The calculation of block discovery rate should be completely independent of both the difficulty, and where we are within a given 2016 block period. So, why should we inevitably see more variation in hash rate at the beginning of a 2016 block period? What you're suggesting is that T (the 'period' you mentioned) automatically resets to zero at the end of a 2016 block period. Well, I was taking the rate value from bitcoincharts.com, so if that's the way they do it, then yes I would expect a large over or under-estimate *just after* a change of difficulty. For a few days though? That makes no sense at all - think about it.
RandyFolds
Sr. Member
****
Offline Offline

Activity: 434



View Profile
February 18, 2012, 09:28:25 PM
 #7

No, the global hashrate is extrapolated from the rate that blocks are found. A lucky streak will make it look like the hashrate is higher than it actually is.

Beyond that, the sample period is too small immediately following a difficulty change so the numbers are always way off for a few days.

I agree with you first point - it is true that it's block discovery rate, not hashrate, that is directly measured, and that it's possible we're just seeing a lucky period. However, your second point doesn't make any sense: what do you mean by the sample period? The block discovery rate is calculated by adding up N blocks over the past T minutes/hours, and then calculating N/T. The calculation of block discovery rate should be completely independent of both the difficulty, and where we are within a given 2016 block period. So, why should we inevitably see more variation in hash rate at the beginning of a 2016 block period? What you're suggesting is that T (the 'period' you mentioned) automatically resets to zero at the end of a 2016 block period. Well, I was taking the rate value from bitcoincharts.com, so if that's the way they do it, then yes I would expect a large over or under-estimate *just after* a change of difficulty. For a few days though? That makes no sense at all - think about it.


That is the way they do it, and a few days is a small sample period compared to two weeks. Probability, homie...shit's all over the place.

Try out the search function. This has been beaten to death since this forum's inception.

▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
▓▓ ONEDICE.ME ▓▓▓▓▓ BEST DICE EXPERIENCE ▓▓▓▓ PLAY OR INVEST ▓▓▓▓▓▓
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
cpt_howdy
Member
**
Offline Offline

Activity: 70



View Profile
February 18, 2012, 09:54:43 PM
 #8

Right, well I think we're talking at cross-purposes here. I was seeing a big change in the block discovery rate, and attributing it to a real change in network hash; the truth is that the block discovery rate is dictated by the combination of total *real* network hash, and luck, which randomly varies from block to block.
Forget that issue, In the last post I was just trying to point out that this estimation process does not change when the difficulty changes - check out the graph below.



See the changes in difficulty? No indication that they provoke wild changes in the the estimated hash rate.
The-Real-Link
Hero Member
*****
Offline Offline

Activity: 530



View Profile
February 18, 2012, 11:09:34 PM
 #9

That's quite a spike.  I'm going to simply guess a lot of people powered on rigs since the difficulty did not spike so they know they can have two more weeks of "consistent" block generation / earnings.

Oh Loaded, who art up in Mt. Gox, hallowed be thy name!  Thy dollars rain, thy will be done, on BTCUSD.  Give us this day our daily 10% 30%, and forgive the bears, as we have bought their bitcoins.  And lead us into quadruple digits
RandyFolds
Sr. Member
****
Offline Offline

Activity: 434



View Profile
February 19, 2012, 02:03:32 AM
 #10

That's quite a spike.  I'm going to simply guess a lot of people powered on rigs since the difficulty did not spike so they know they can have two more weeks of "consistent" block generation / earnings.

I am failing to see a statistically significant jump in that graph...certainly not 50%.

Why would they have powered off and then powered on with very little change in the situation, save for a drop in the price of BTC, and thus a drop in their profitability?

▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
▓▓ ONEDICE.ME ▓▓▓▓▓ BEST DICE EXPERIENCE ▓▓▓▓ PLAY OR INVEST ▓▓▓▓▓▓
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
The-Real-Link
Hero Member
*****
Offline Offline

Activity: 530



View Profile
February 19, 2012, 07:25:32 AM
 #11

That's quite a spike.  I'm going to simply guess a lot of people powered on rigs since the difficulty did not spike so they know they can have two more weeks of "consistent" block generation / earnings.

I am failing to see a statistically significant jump in that graph...certainly not 50%.

Why would they have powered off and then powered on with very little change in the situation, save for a drop in the price of BTC, and thus a drop in their profitability?

Perhaps they thought the difficulty would spike upwards and decrease their profits even further?  Who knows?  While there can be good estimation on all of this, it's seemingly as much speculation as it is fact sometimes.

Oh Loaded, who art up in Mt. Gox, hallowed be thy name!  Thy dollars rain, thy will be done, on BTCUSD.  Give us this day our daily 10% 30%, and forgive the bears, as we have bought their bitcoins.  And lead us into quadruple digits
Littleshop
Legendary
*
Offline Offline

Activity: 1316



View Profile WWW
February 20, 2012, 12:10:26 AM
 #12

These threads appeared every difficulty change for a while but we went a bit without them. 

The rate did not rise dramatically. It is just the formula used to display the hash rate. 



BinaryMage
Hero Member
*****
Offline Offline

Activity: 546


Ad astra.


View Profile
February 20, 2012, 05:22:34 PM
 #13

And voila, back to normal. Worry less, think more.  Wink

-- BinaryMage -- | OTC | PGP
joulesbeef
Sr. Member
****
Offline Offline

Activity: 476


moOo


View Profile
February 20, 2012, 06:13:36 PM
 #14

And voila, back to normal. Worry less, think more.  Wink


That's what THEY would like you to think.

mooo for rent
DeathAndTaxes
Donator
Legendary
*
Offline Offline

Activity: 1218


Gerald Davis


View Profile
February 20, 2012, 06:35:39 PM
 #15

These threads appeared every difficulty change for a while but we went a bit without them. 

The rate did not rise dramatically. It is just the formula used to display the hash rate. 

Yeah they make a good difficulty change alarm.  I knew what the thread, proposed scenario, and real outcome was before clicking.  Good news is I learned we just had a difficulty adjustment and it was flat so wasn't a wasted thread.
DeathAndTaxes
Donator
Legendary
*
Offline Offline

Activity: 1218


Gerald Davis


View Profile
February 20, 2012, 06:37:40 PM
 #16

See the changes in difficulty? No indication that they provoke wild changes in the the estimated hash rate.

See a 15TH data point there?

My guess is you got your "15TH/s" from somewhere else.  Somewhere that to avoid complex calculations simply compared # of blocks and timespan since last difficulty reset.  Why since last difficulty reset?  It avoids having to do more complex calculations involving multiple difficulties.  Those sites tend to be insanely in accurate in the first 30 or so blocks after difficulty change.

Care to point out where you saw "15TH/s"?
RandyFolds
Sr. Member
****
Offline Offline

Activity: 434



View Profile
February 20, 2012, 11:01:40 PM
 #17

See the changes in difficulty? No indication that they provoke wild changes in the the estimated hash rate.

See a 15TH data point there?

My guess is you got your "15TH/s" from somewhere else.  Somewhere that to avoid complex calculations simply looks at blocks and time since last difficulty reset (it avoids needing to adjust for multiple difficulty values).  Those sites tend to be insanely in accurate in the first 30 or so blocks after difficulty change.

Care to point out where you say 15TH/s?


Doesn't it feel good to be right? I rarely have the luxury, but when I do...oh boy...

▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
▓▓ ONEDICE.ME ▓▓▓▓▓ BEST DICE EXPERIENCE ▓▓▓▓ PLAY OR INVEST ▓▓▓▓▓▓
▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
eleuthria
Legendary
*
Offline Offline

Activity: 1750


BTC Guild Owner


View Profile WWW
February 21, 2012, 06:31:19 PM
 #18

Deepbit's luck for last 24h is 20% better than expected, so I can believe that this spike is caused by luck.

BTC Guild also had extremely good luck on the 18th (and some of the 19th).  Of course then we had a 6 hour block and 10 hour block yesterday/today.  Luck can have a dramatic influence on the rate of blocks in a short window (and 24 hours is DEFINITELY short).

R.I.P. BTC Guild, 2011 - 2015.
BTC Guild Forum Thread
Pages: [1]
  Print  
 
Jump to:  

Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!