* core: move TxPool reorg and events to background goroutine
This change moves internal queue re-shuffling work in TxPool to a
background goroutine, TxPool.runReorg. Requests to execute runReorg are
accumulated by the new scheduleReorgLoop. The new loop also accumulates
transaction events.
The motivation for this change is making sends to txFeed synchronous
instead of sending them in one-off goroutines launched by 'add' and
'promoteExecutables'. If a downstream consumer of txFeed is blocked for
a while, reorg requests and events will queue up.
* core: remove homestead check in TxPool
This change removes tracking of the homestead block number from TxPool.
The homestead field was used to enforce minimum gas of 53000 for
contract creations after the homestead fork, but not before it. Since
nobody would want configure a non-homestead chain nowadays and contract
creations usually take more than 53000 gas, the extra correctness is
redundant and can be removed.
* core: fixes for review comments
* core: remove BenchmarkPoolInsert
This is useless now because there is no separate code path for
individual transactions anymore.
* core: fix pending counter metric
* core: fix pool tests
* core: dedup txpool announced events, discard stales
* core: reorg tx promotion/demotion to avoid weird pending gaps
* core: use a wrapped `map` and `sync.RWMutex` for `TxPool.all` to remove contention in `TxPool.Get`.
* core: Remove redundant `txLookup.Find` and improve comments on txLookup methods.
This PR implements the new LES protocol version extensions:
* new and more efficient Merkle proofs reply format (when replying to
a multiple Merkle proofs request, we just send a single set of trie
nodes containing all necessary nodes)
* BBT (BloomBitsTrie) works similarly to the existing CHT and contains
the bloombits search data to speed up log searches
* GetTxStatusMsg returns the inclusion position or the
pending/queued/unknown state of a transaction referenced by hash
* an optional signature of new block data (number/hash/td) can be
included in AnnounceMsg to provide an option for "very light
clients" (mobile/embedded devices) to skip expensive Ethash check
and accept multiple signatures of somewhat trusted servers (still a
lot better than trusting a single server completely and retrieving
everything through RPC). The new client mode is not implemented in
this PR, just the protocol extension.
