On Saturday, March 03, 2012 6:51:34 PM Geir Harald Hansen wrote: > Long polling as currently implemented in pools has a race condition. > Does the miner reconnect first or does another block change happen > first? "Double" block changes are common with merged mining and I'm > doing all sorts of tricks in my pool backend to reduce this problem.
How would you suggest addressing this? I presume if a share solves blocks on multiple chains, you just longpoll once when that's successful? > How about another entry "longpollid" in long poll responses. The last > seen longpollid should be included by the client in future long poll > requests. This enables the server to see if the client has missed any > block changes. The ID could perhaps be submitted in an HTTP header > (X-LongPollID?) if we wish to keep the JSON-RPC params empty, or params > could hold an object with a key "longpollid". Could be a string or > number, like "workid". Hmm, the problem is that adding any parameters to getmemorypool itself breaks compatibility with bitcoind 0.5, and using HTTP headers makes it HTTP-specific again. Any ideas? > Another useful value in the getmemorypool response would be "height", so > the miner can include the correct height in the coinbase. I would like > that in bitcoind as well. One JSON-RPC call instead of two, and no race > condition between getmemorypool and getblocknumber. Good catch. Should this be required (since it might be necessary for future Bitcoin blocks), or just "should" for compatibility? > It should be explained how target vs. fulltarget works. What is unclear about this? > Perhaps some things should be optional for a client to implement? Doing this safely needs some way for clients to communicate capabilities to the server, which has the problem of passing parameters to getmemorypool. > I think "noncerange" is of limited use and there's a good chance of getting > the endianness wrong. There is no mining hardware to date that exhausts even half the nonce space, so I'd really prefer to see this as a required feature on the miner side. On the other hand, it's merely an extension for getwork, so I can see the problem so long as we're using getwork proxies. Luke ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development