Topic: [4+ EH] Slush Pool (slushpool.com); Overt AsicBoost; World First Mining Pool - page 793. (Read 4382675 times)

Hi, to change your OVH password, you need to go to the backoffice. An email is sent to the email adresse with an unique URL.
This URL is formed by 21 chars using 3 differents RAND algorythm, which every algorythim create 7 chars (7x3 = 21). After this, the client receive an email with this unique URL

[snip]

This is a procedure used since 7 years who didn't change.

[snip]

The 26th april, we (OVH) saw this problem. 2 of the 3 functions who generate the RAND number where "not really rand" (quick translate). So this "unique" URL can be bruteforced (only 1/3 of the string was RAND).
This problem has been discovered the 26th of April, at 11:03:14 (Maybe French hours, GMT +1?) and has been fixed at 12:54:13.
A patch have been developped to use a corrected RAND functions.
Some change has been made to use 2 reals new RAND functions/algo.

[snip]

After, we made a big search in our database to find if other clients have been compromised, during the last 3 years. (OVH is allowed to keep 10 years of logs, according to CNIL Agreement (Wikipedia CNIL : http://en.wikipedia.org/wiki/CNIL )). Now we (OVH) are going back to 10 years to be sure...

[snip]

(personal note) : More about the hack & Bitcoin cumminity

We found 3 ID who has been hacked, in this 3 cases, the "bitcoin" cummunity was targeted who was using OVH services. The hacker found the exploit the 23th of April, at 22h, testing during an hour. At 23h, the exploit method was working and the first OVH ID has been hacked. The day after, 2 others Bitcoin OVH ID has been hack.

We have been in contact with this clients, but the quality of the exchanges didn't help us to find the problem/security hole. One of our internal dev finally found the hole and fixed it. We certainly must find some lessons to learn in the way to speak with our customers in this kind of problems.

[snip] (Line 72 on pastebin)

It took a long time to communicate about this, because we seen it was a really "small" effect (not sure about my translation in this) but "only 3 clients", and we wanted to check completly if there was only 3 clients affected or more, before speaking about this issue...

[snip] Since Line 86, more "commercial" speaking, I'll not translate it.

Idiot employee drooped it because he felled the need to move it...

a whole bunch of stuff...

If you are having problems with your miner, you should probably get those resolved first before complaining about what slush is doing.  Seriously, when my miners are stable, which is almost all the time, my payouts are constant and regular.  I've never had to worry about the score normalizing.

sadly your argument is the opposite of what it's meant to be, you just described the very actions that the score system are trying to deter. And if people were doing that he would have to make the functions even harsher.

That is the way it is though if your on a 4h block you can get 99% payout just being on the last hour.  There has to be some way of determining how long you were connected and calculate off that?

OK then way my scores goes to 0? If it was renormalisation it would be some small number... And since I have a lot of problems with my miner right now I see score 0 toooooo many times right now...

Not how the "reset" works. It's more of a "renormalisation".

I suspect you are being hasty in blaming stratum.  My CGMiner instances - 5 of them, have been running on slush's pool continuously for over a month with stratum without any downtime.

There are some resets of the scores also so after a reset you don't get any... 90 minutes is more then enough for reset to accrue... Probably more then once. So even 1000 ASIC wouldn't help... That way I was asking for pool to have a maintenance mode and that way I'm using backup PPS pool in time of maintenance... And also why backup pool is PPS. So I get something out... If the backup pool would use Slush method for short outage I would get close to 0. But then again I could be lucky... For some time I used PPLNS method but I got out about 10% of what I lost so PPS is probably much better... But then again I might be wrong...

Ok, I am surprised that the scoring system works that way....

It means even if I am an ASIC miner if I have an outage of 90minutes due to a storm then I lose all my shares value. Everyone else profited from my shares. So down time is my enemy.

How does the score system work? (I am sorry for my ignorance!)

sadly your argument is the opposite of what it's meant to be, you just described the very actions that the score system are trying to deter. And if people were doing that he would have to make the functions even harsher.

Ok, I am surprised that the scoring system works that way....

It means even if I am an ASIC miner if I have an outage of 90minutes due to a storm then I lose all my shares value. Everyone else profited from my shares. So down time is my enemy.

How does the score system work? (I am sorry for my ignorance!)

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The thing that came to mind though is the following after being surprised by this part of the score system:

If I run really high difficulty shares...let say 512...and I therefore submit larger shares but less frequently...is this the reason why I earn alot less?

I noticed if I submit very low difficulty shares with a very high frequency...my score seems to stay very low (closer to 100 than 1 billion. Yet, if I submit shares at 512 difficulty every minute, my score goes into the hundreds of millions over time. I assume from watching this that my delay in submitting very high difficulty shares is actually hurting me in my score. Is this correct? If so, then this deeply discourages using high difficulty...right? I can see this turning into an ASIC-festival of people submitting diff1 shares. With BFL coming out and delivering (a minute amount) of ASICs...I assume this is going to be a bandwidth problem in the future, correct?

I eventually decided to run at diff-1 because the super short rounds didn't give me much of any chance as an ASIC to submit the higher difficulty shares.

I find myself scratching my head as what is the right thing to do. It seems to discourage any lapse in submitting shares, even if only a minute between submissions.

I also understood that a low score in 4 digits is better than a high score in the billions. Correct?

I know why the functions are there, but its effects do seem a little harsh. Maybe it could be reduced a little? Otherwise those with massive rigs could switch do the opposite of the normal problem, run them on a PPS pool, then they notice its been 45 minutes here switch.

Yes I found those the other day and thought they were excellent as well.  (When is the next one coming out?)

I kept seeing blocks that had under-calculated (by a lot) and it was bugging me until I found those.

The TL;DR version is that in order to prevent pool hopping Slush's scoring mechanism rewards shares found later in the round more than shares found earlier in the round.  This mechanism as implemented also introduces variance in the pay out.  Sometimes you get more than expected for a block and sometimes you get less as compared to a purely proportional payout system.  To check, look at your highest and lowest rewards over time and you should find some lower and some higher than the value calculated by this formula: (Block Value * 0.98 * your shares) / total shares

If you are a full-time miner however, the long term effect of the variance will disappear and your long term reward will look almost identical to what it would if that formula above were actually being used.  The end result is that pool hopping from Slush's pool is only profitable to a very, very tiny degree and full time miners are not losing much reward to pool hoppers. 

Slush could lower that pool hopping profitability even more but it would raise the payout variance even more which would make some blocks look even worse.

Very good read indeed. I wonder how many of the forum members will take the time to read & understand (!) it. I see a rather wide spectrum of skills and attitude and many reoccurring questions that makes me assume the majority will just skip anything longer than a few paragraphs. Anyway, congratulations, I really recognize the full worth of these quality articles.

Cheers,
   T

4.2 and 4.3 are the important ones - 4.1 is just background. They are from last year, but the score method is the same now as it was then.

Probably shouldn't comment since I haven't had a chance to read those yet, but I did mention above about how I thought the system was outdated.
Judging by the hash rates in the top of those they aren't very recent.
If im wrong, please dont hang me! I'll apologise for my ignorance once I have had time to look at things properly.