Each server has a slightly different coinbase message, so there is no chance of duplicated work.

Thank you for that.  I forgot to re-enable idle miner scripts once all the time zone issues were fixed.

Each Stratum server has a local bitcoind to keep them from having a central point of failure.  Additionally there is a hot wallet for payouts that is separate from those and a store wallet.

Yeah, average bandwidth is quite low.  The server has a large burst roughly ever 30 seconds [push out updated work], but it's so brief it barely impacts the overall average.  This also includes a total of 6 bitcoind nodes between the various servers.

Average bandwidth for the last 30 days [US Stratum+Website]:  14.2 mbps in, 16.3 mbps out.

Renaming workers is normally instant, unless you try to connect to the pool with the new name prior to the rename.  The pool caches a list of bad worker credentials so it doesn't bother connecting to the database to validate constant bad attempts.

No, higher difficulty does not mean higher stales.  Stales are not the same as discarded work.  Discarded is a USELESS, 100% MEANINGLESS statistic when mining on Stratum.

Discarded shares are meaningless for stratum.  The statistic means absolutely nothing to you unless you're on getwork.  Just ignore it.

Site has been extremely fast here, there isn't even a slow period when scripts run anymore.  Sounds like you may have had a bad connection to the cloudflare server that you were directed at.

BTC Guild was the first pool to deploy variable difficulty, and if you do not adequately set your minimum difficulty, the pool will adjust it for you.  That is why the setting is labelled "MINIMUM difficulty".  BTC Guild uses a 20-40 Shares Per Minute range (it doubles your difficulty any time you hit 40 SPM for a 5 minute duration).

For those running the stratum proxy, the problem is due to the proxy sending the authorization prior to the subscribe.  If you want to get your hands dirty, it shouldn't be too hard to edit the proxy code to put these in the correct order.

The PPLNS stats page shows our luck this difficulty, and also our luck split into 10-shift segments (~8 hour intervals).

Brief attack on the pool affecting one of the US servers.  Most users' mining clients seemed route around it quite quickly before I was even woken up by my alarms.

PPLNS isn't affected by your connection going on/off.  The expected value of your share is determined over the 8 hours subsequent to submitting that share.  Whether you disconnect or not, that has no effect on the expected value of your shares, which is 4.5% higher than PPS (not counting NMC).

Although I would agree that if you're only using the pool as a failover, PPS would probably be the way to go.

For miners on BTC Guild, PPLNS will always pay better in the long run.  You get 4.5% lower fee and NMC on top of that.  You just need to step back and look at the bigger picture rather than dwell on day to day luck.  BTC Guild is large enough that we are almost always within the expected variance.  Even when our luck for an entire difficulty is pretty bad, it almost alwaysl pays out ahead of PPS in the same period.

For me, PPS is obviously better since I make more off you, but the flip side of that is I have to keep a larger hot wallet, and then stop my head from exploding if I lose 100-200 BTC in a day due to bad luck.  I'm much happier making less and not having to go through the stress of ups & downs on pool wide variance.

Funny looking back, was so happy at the first 30 GH/s, and 300 GH/s .  300 GH/s was one of the first big bottlenecks for the old pool software!

It depends on the size of the pools you're testing.  For a pool like BTC Guild, 2-4 weeks would be adequate.  We haven't had a 2016 block period end more than +/- 10% in months.

However, smaller pools will require MUCH more time.  Your results are pretty much guaranteed to vary greatly even on the same pool from month to month.

If the difficulty of your share is more than the NMC difficulty, it will solve an NMC block.  If it is higher than the BTC difficulty, it will also solve a BTC block.  Since BTC Diff is more than NMC Diff, finding one that is >= BTC diff will always be >= NMC as well.

Bitstamp (and all other EXCHANGES as far as I'm aware) does not actually keep a balance in the deposit address they give you.  It's simply one address generated in their bitcoin instance that they marked as belonging to you when a deposit is sent to it.  When they send money to other users for withdrawals, there is a chance that the funds will originate from your deposit address.

Basically exchange wallets are a giant safe with lots of little slots for depositors.  Money from people depositing into exchanges to in a slot designated for that user, but then they're just in a giant pile and get pulled from as needed to fund other users' withdrawals and/or moved to cold storage.  They internally keep track of what balance each user is entitled to pull out of the money pile upon request.

Update for the 24 hour earnings statistic:  PPS users had their 24 hour earnings counters reset during the database migration, so please do not freak out over the fact that it is only showing a fraction of what it should be showing.