Multipool - the pool mining pool (with source code)

[gentakin]

So, how does it compare to the other large and not-unfair pools after a couple of days of being on it?

Right now it seems to be pulling 90%+ of getworks from BTC Guild. This is probably because their share stats are way off (saying the current round has 5k shares, while it's already taking 43mins).

When it showed correct values earlier today, and after eligius-eu found a block, only 2 of my shares were sent to eligius. So I guess the hopping is still not quite perfect. It's not that much profitable for me, but probably somewhat better than using a single pool.

[Elokane]

I wonder if you're the ones who broke their server.

[techwtf]

132174   Tue Jun 21 00:32:17 2011   246   258.809   0.00000000   0.000   0.00000000
132143   Mon Jun 20 21:41:42 2011   445   433.462   0.01714037   0.676   0.00000000
132128   Mon Jun 20 19:37:20 2011   185   184.074   0.02919802   2.768   0.00098159
132122   Mon Jun 20 18:46:13 2011   1   2.028   0.00000000   0.000   0.00000000
132116   Mon Jun 20 17:59:25 2011   636   619.802   0.00000003   0.000   0.00000000
132071   Mon Jun 20 13:05:30 2011   63   93.200   0.04334367   12.067   0.00209219
132070   Mon Jun 20 12:50:42 2011   162   159.564   0.00000000   0.000   0.00000000
132061   Mon Jun 20 12:00:13 2011   5   5.261   0.00057064   2.002   0.00001503
132026   Mon Jun 20 09:00:12 2011   724   692.000   0.00000000   0.000   0.00000000
131978   Mon Jun 20 03:53:09 2011   85   77.960   0.00702898   1.450   0.00011488
131905   Sun Jun 19 20:21:54 2011   569   550.916   0.00000000   0.000   0.00000000

Why so many 0.00 eff shares from btcmine... that's like 100% fee.
I dont think there are so many invalid blocks.

[gentakin]

BTC mine uses a score-based reward scheme to prevent pool hopping (which is a good thing).

That means all submitted shares lose their value over time. New shares are worth more while old shares are worth less. After some time, old shares are worth nothing. So 0.000000 might be correct. (Or maybe it's just a parsing problem. If that's the case, it will probably be fixed later.)

[Coaster]

132174   Tue Jun 21 00:32:17 2011   246   258.809   0.00000000   0.000   0.00000000
132143   Mon Jun 20 21:41:42 2011   445   433.462   0.01714037   0.676   0.00000000
132128   Mon Jun 20 19:37:20 2011   185   184.074   0.02919802   2.768   0.00098159
132122   Mon Jun 20 18:46:13 2011   1   2.028   0.00000000   0.000   0.00000000
132116   Mon Jun 20 17:59:25 2011   636   619.802   0.00000003   0.000   0.00000000
132071   Mon Jun 20 13:05:30 2011   63   93.200   0.04334367   12.067   0.00209219
132070   Mon Jun 20 12:50:42 2011   162   159.564   0.00000000   0.000   0.00000000
132061   Mon Jun 20 12:00:13 2011   5   5.261   0.00057064   2.002   0.00001503
132026   Mon Jun 20 09:00:12 2011   724   692.000   0.00000000   0.000   0.00000000
131978   Mon Jun 20 03:53:09 2011   85   77.960   0.00702898   1.450   0.00011488
131905   Sun Jun 19 20:21:54 2011   569   550.916   0.00000000   0.000   0.00000000

Why so many 0.00 eff shares from btcmine... that's like 100% fee.
I dont think there are so many invalid blocks.

reported earlier was that btcmine's scrape of stats was not 100% working, in due time when they get paid out, you should see correct stats appear (hopefully) otherwise were gettin juked...
and heres an update for my top stats in case anyone wants to compare. I don't leave these 2 miners running multipool all day.. I run it mornings and afternoons only.
Shares   4153
Shares (pending)   5901
Utility   5015.606
Earned   0.33042518
Efficiency   1.395
Collected   0.11301604
Paid   0.00000000
Date   Tue Jun 21 16:34:19 2011

[Mike 71]

My Efficiency went town from 1.33 (before 12 hours) to 1.15. What means below 1 for today. I hope the btcmine data are incorrect!

I calculated my possible income on average and must say, with both pcs running 24 hours i can expect .43 Bitcoins (380 MHash/s). It feels low on multipool, but after looking to the pending stats all should be fine, but still not seeing a big win.

But i really like it reading your daily update! Keep on coding!

[iopq]

My Efficiency went town from 1.33 (before 12 hours) to 1.15. What means below 1 for today. I hope the btcmine data are incorrect!

I calculated my possible income on average and must say, with both pcs running 24 hours i can expect .43 Bitcoins (380 MHash/s). It feels low on multipool, but after looking to the pending stats all should be fine, but still not seeing a big win.

But i really like it reading your daily update! Keep on coding!

efficiency goes up and down depending on how fast pools reward you

[Multipool]

Another set of payouts is out! Since sendmany transactions are apparently very cheap, the payout minimums have been relaxed to 0.10 BTC daily, or 0.01 BTC after 3 days of inactivity. I could probably even go down to 0.01 BTC daily next time.

Squashed a nasty little bug (wrong variable name at just the wrong place) in the last getwork module update that caused submitted shares to be re-routed to the last pool a user received work from, rather than the actual pool, leading to invalid shares. The final effect wasn't too bad though: the pools quickly fought it out with each other, until btcguild emerged victorious and served most of the shares for the rest of the day while the other pools cooled in the penalty box. With the fix, you should have seen much fewer invalid shares, and better pool rotation.

To anyone complaining about zero efficiency on btcmine - there are three reasons:

• btcmine rounds are "debited" sometime after they are "confirmed". Efficiency will sit at zero for up to an hour until the btcmine money status page gets updated.
• Value of shares decays exponentially. If efficiency is low but non-zero, you are probably looking at old shares in a long round.
• The "money" page is not really synchronous with anything. Multipool makes best effort to guess which round each particular debit applies too, but it isn't perfect. I've checked manually just now, but only found one possible mistake (round 132174 didn't get "debited"). Even manually I cannot sort out how much it should have been worth.
  

But that's all besides the point because we are apparently banned at btcmine, and also at deepbit, bitcoinpool, and possibly slush. In all four cases it appears to have been automatic rather than intentional. Considering how much workload and DoS some of the pools have been struggling with, it may be understandable if their scripts see 20GH/s worth of requests as another DoS attack and block it. As has been predicted, Multipool is being undone by its own success .

[Meni Rosenfeld]

But that's all besides the point because we are apparently banned at btcmine, and also at deepbit, bitcoinpool, and possibly slush. In all four cases it appears to have been automatic rather than intentional. Considering how much workload and DoS some of the pools have been struggling with, it may be understandable if their scripts see 20GH/s worth of requests as another DoS attack and block it. As has been predicted, Multipool is being undone by its own success .

Can't you use several account per pool, from different IPs (using some proxy service)? And can you try to do the hopping more gentle, at the cost of some efficiency but becoming less conspicuous?

[techwtf]

Sorry to hear that multipool is banned ... switched back to bitcoins.lc . Why not drop btcmine...
If a pool's efficiency always less than 0.9, even PPS in deepbit is better than that...

Pool: btcmine
Shares: 6079
Utility: 6126.203
Earned: 0.21746285
Efficiency: 0.627

~6000 shares -> 0.217 BTC...

[Multipool]

Why not drop btcmine...
If a pool's efficiency always less than 0.9, even PPS in deepbit is better than that...

Pool: btcmine
Shares: 6079
Utility: 6126.203
Efficiency: 0.627

We cannot drop btcmine for having lower efficiency than other pools. Being a score-based pool, it provides an important role - a baseline expected utility of about 90%. All the times you are mining in btcmine at 90% utility, all the other pools have utilities much lower than that - you would lose more by removing btcmine from rotation. Btcmine also has a very good response rate, so it often fills in extra getworks when a higher-utility pool cannot keep up. Notice that for most rounds in btcmine, the expected utility actually is just about or slightly higher than 100%. Unless you can show with statistical significance that the actual btcmine rewards, and therefore efficiency, are lower than the predicted utility, it has to stay.

An even better alternative would be a constant-utility pool like Continuum, but I am afraid whether doubling its hashrate is such a good idea. Continuum is a good fallback for solo hoppers, but we, as a pool of comparable size, would not gain much decrease in block finding variance by joining up. We would be better off generating our own getworks, which, by definition, have expected utility of 100%... Perhaps I'll increase the priority of generated getworks over pools with utilities below 100% (right now solo getworks only get used as a fallback to keep the work queue running).

[organofcorti]

I thought some might find this interesting. If, on the other hand you're not into chart porn, just pretend it's spam and go to the next post.

1. The first graph shows my earnings over time - quite linear, the ups and downs in efficiency you see daily are a bit misleading.

2. The second is the most interesting - the model that fits this does so with an adj R2 of 0.4 and a p-val<10^-12.
The log-log linear model:
y=3.16260-0.63700*x
Solving for unity (ie efficiency=1)
x=4.97
blocks=exp(4.97) = 143

So for BTCGuild, with me at 700Mhash/sec, more blocks than 143 accepted shares will reduce efficiency for all blocks shares for that round (ninja edit!). Interesting, but not very useful.

3. and 4. are also very interesting looking, but fairly useless. Efficiency and coins will always be higher for shorter rounds (outliers mostly due to multipool downtime). It would be nice to be able to compare what they would have been had I contributed my shares to BTCGuild normally though. So.....

Multipool, if you could give me the total shares from each pool for the block (I know, more scraping), I might be able to look at where maxima in efficiency  are for the various pools. If you can give me data for the pool as a whole, it may even be handy for you! And (I know I'm pressing my luck here) if you can give a separate url for each pool, I can automate the process (the language I use doesn't like html scraping anything other than one table at a time, and I have to edit by hand).

[techwtf]

To get more fees, solve the problems first to boost eff
I'll be back later.

[organofcorti]

To get more fees, solve the problems first to boost eff
I'll be back later.

At worst, think of multipool as a zero variance pool with lower fees than deepbit. So far I've made 3.58 coins from 54824 shares. On average, you should only expect  0.000057 coins/share at current difficulty. so the expected coins from 54824 shares = 3.12 coins

expected coins: 3.12
earned coins: 3.58

So, I'm ahead by 14.7%. Even if efficiency = 1, the low variability would be my reason to stay.

What are your expected and actual earnings, techwtf?

[TeaRex]

There seems to be a little math problem in your Webserver script at the moment.

My total utility is currently "nan" (http://en.wikipedia.org/wiki/NaN) probably thanks to the fact that Utility at eligius-eu is "nan", which in turn is caused by utility for the 325 shares I submitted there (through multipool of course) for block #132521 being "nan" for whatever reason.

And let me offer a little suggestion: It would be nice if instead of "utility" you'd have "expected efficiency" (i.e. utility divided by number of submitted shares) listed on the site. That way one could compare it directly with the achieved efficiency without having to do all the divisions by hand (or rather in the Windows calculator...).

Also, is there any particular reason that bitcoinpool is listed twice?

I'm mining on Multipool under the address 1Jp9L4vkdkpFBmUWrBQcwj5rFSrmpzc19F if you need that info to check the problems yourself.

Thanks again for offering this service!

[techwtf]

To get more fees, solve the problems first to boost eff
I'll be back later.

At worst, think of multipool as a zero variance pool with lower fees than deepbit. So far I've made 3.58 coins from 54824 shares. On average, you should only expect  0.000057 coins/share at current difficulty. so the expected coins from 54824 shares = 3.12 coins

expected coins: 3.12
earned coins: 3.58

So, I'm ahead by 14.7%. Even if efficiency = 1, the low variability would be my reason to stay.

What are your expected and actual earnings, techwtf?

Sure. the eff is nice & > 1 (1.086) in general. It's just ONE pool's consistent poor performance that makes me leave(& with many shares).

I'm getting ~0.55/day at the beginning of the diff change, with 400M/s(should get 0.48 with 0 fee).
My first day of multipool with 0 earning, second day 0.32, third day 0.39(all paid out amount). sure, it's becoming better. just expected no eff < 0.8 pool. Watching so many shares becomes 0 BTC is really unacceptable...

[Mike 71]

Sure. the eff is nice & > 1 (1.086) in general. It's just ONE pool's consistent poor performance that makes me leave(& with many shares).

I'm getting ~0.55/day at the beginning of the diff change, with 400M/s(should get 0.48 with 0 fee).
My first day of multipool with 0 earning, second day 0.32, third day 0.39(all paid out amount). sure, it's becoming better. just expected no eff < 0.8 pool. Watching so many shares becomes 0 BTC is really unacceptable...

If you mine solo, every share that did not solve the block becomes 0 BTC. Scoring system have more variance than sharebased ones, not as much as solo mining but still many shares becomes worthless or almost worthless.

Seeing 400 Shares efficiency 0 is OK for me if i see 400 other shares with efficiency 2. Or 200 with efficiency 4, you know.
I think we just had 'bad luck', because its a big variance in hopping to btcmine. I am sure that will change over time. Anyway, i like the idea of this pool and just wait for news from this pool, so unless i really loss much i will stay here.

@multipool: For those bans: you going to implement the proxy for clients you talked about?
Maybe you can implement a more smooth poolchanging. Like working on the weighted 50% of the pools with better actuall utility for example. This will lower the theretical effect without bans but may perform better.

Greetings
Mike

[organofcorti]

To get more fees, solve the problems first to boost eff
I'll be back later.

At worst, think of multipool as a zero variance pool with lower fees than deepbit. So far I've made 3.58 coins from 54824 shares. On average, you should only expect  0.000057 coins/share at current difficulty. so the expected coins from 54824 shares = 3.12 coins

expected coins: 3.12
earned coins: 3.58

So, I'm ahead by 14.7%. Even if efficiency = 1, the low variability would be my reason to stay.

What are your expected and actual earnings, techwtf?

Sure. the eff is nice & > 1 (1.086) in general. It's just ONE pool's consistent poor performance that makes me leave(& with many shares).

I'm getting ~0.55/day at the beginning of the diff change, with 400M/s(should get 0.48 with 0 fee).
My first day of multipool with 0 earning, second day 0.32, third day 0.39(all paid out amount). sure, it's becoming better. just expected no eff < 0.8 pool. Watching so many shares becomes 0 BTC is really unacceptable...

Sorry techwtf, I still don't get why you'd leave for losing some shares to btcmine - you get decaying shares at eligius-eu which zero out some rounds. But the overall efficiency for eligius-eu is ok, as is the overall efficiency for the pool.

Can you post your shares (without pending, the top number) and your earned (not collected) for all pools?  Efficiency of 1.086 is not just nice, but means you get 1.086 coins for every coin you'd earn elsewhere (averaged over quite often a loooong period of time).

[organofcorti]

There seems to be a little math problem in your Webserver script at the moment.

My total utility is currently "nan" (http://en.wikipedia.org/wiki/NaN) probably thanks to the fact that Utility at eligius-eu is "nan", which in turn is caused by utility for the 325 shares I submitted there (through multipool of course) for block #132521 being "nan" for whatever reason.

And let me offer a little suggestion: It would be nice if instead of "utility" you'd have "expected efficiency" (i.e. utility divided by number of submitted shares) listed on the site. That way one could compare it directly with the achieved efficiency without having to do all the divisions by hand (or rather in the Windows calculator...).

Also, is there any particular reason that bitcoinpool is listed twice?

I'm mining on Multipool under the address 1Jp9L4vkdkpFBmUWrBQcwj5rFSrmpzc19F if you need that info to check the problems yourself.

Thanks again for offering this service!

NotaNumber (div by zero) just ruin everything! they're contagious and infect everything they contact.

Can anyone explain what utility is? Efficiency is how many expected shares worth of coin your actual shares get you, but I can't figure out how to relate utility to shares.  And I don't understand what TeaRex means here (no offence mate) since I don't know how you could get an "expected efficiency".

[iopq]

Why not drop btcmine...
If a pool's efficiency always less than 0.9, even PPS in deepbit is better than that...

Pool: btcmine
Shares: 6079
Utility: 6126.203
Efficiency: 0.627

We cannot drop btcmine for having lower efficiency than other pools. Being a score-based pool, it provides an important role - a baseline expected utility of about 90%. All the times you are mining in btcmine at 90% utility, all the other pools have utilities much lower than that - you would lose more by removing btcmine from rotation. Btcmine also has a very good response rate, so it often fills in extra getworks when a higher-utility pool cannot keep up. Notice that for most rounds in btcmine, the expected utility actually is just about or slightly higher than 100%. Unless you can show with statistical significance that the actual btcmine rewards, and therefore efficiency, are lower than the predicted utility, it has to stay.

An even better alternative would be a constant-utility pool like Continuum, but I am afraid whether doubling its hashrate is such a good idea. Continuum is a good fallback for solo hoppers, but we, as a pool of comparable size, would not gain much decrease in block finding variance by joining up. We would be better off generating our own getworks, which, by definition, have expected utility of 100%... Perhaps I'll increase the priority of generated getworks over pools with utilities below 100% (right now solo getworks only get used as a fallback to keep the work queue running).

just generate own getworks when utility is low, then the average utility is always high
with 20 ghash/s we should be able to solve our own block every couple of days

and of course I love the suggestion for proportional shares for the solo pool, it's so deliciously ironic