* consensus/ethash: add maxEpoch constant
* consensus/ethash: improve cache/dataset handling
There are two fixes in this commit:
Unmap the memory through a finalizer like the libethash wrapper did. The
release logic was incorrect and freed the memory while it was being
used, leading to crashes like in #14495 or #14943.
Track caches and datasets using simplelru instead of reinventing LRU
logic. This should make it easier to see whether it's correct.
* consensus/ethash: restore 'future item' logic in lru
* consensus/ethash: use mmap even in test mode
This makes it possible to shorten the time taken for TestCacheFileEvict.
* consensus/ethash: shuffle func calc*Size comments around
* consensus/ethash: ensure future cache/dataset is in the lru cache
* consensus/ethash: add issue link to the new test
* consensus/ethash: fix vet
* consensus/ethash: fix test
* consensus: tiny issue + nitpick fixes
* cmd, consensus, eth: split ethash related config to it own
* eth, consensus: minor polish
* eth, consenus, console: compress pow testing config field to single one
* consensus, eth: document pow mode
This PR polishes the EIP 100 difficulty adjustment algorithm
to match the same mechanisms as the Homestead was implemented
to keep the code uniform. It also avoids a few memory allocs
by reusing big1 and big2, pulling it out of the common package
and into ethash.
The commit also fixes chain maker to forward the uncle hash
when creating a simulated chain (it wasn't needed until now
so we just skipped a copy there).
This commit is a preparation for the upcoming metropolis hardfork. It
prepares the state, core and vm packages such that integration with
metropolis becomes less of a hassle.
* Difficulty calculation requires header instead of individual
parameters
* statedb.StartRecord renamed to statedb.Prepare and added Finalise
method required by metropolis, which removes unwanted accounts from
the state (i.e. selfdestruct)
* State keeps record of destructed objects (in addition to dirty
objects)
* core/vm pre-compiles may now return errors
* core/vm pre-compiles gas check now take the full byte slice as argument
instead of just the size
* core/vm now keeps several hard-fork instruction tables instead of a
single instruction table and removes the need for hard-fork checks in
the instructions
* core/vm contains a empty restruction function which is added in
preparation of metropolis write-only mode operations
* Adds the bn256 curve
* Adds and sets the metropolis chain config block parameters (2^64-1)
This commit adds pluggable consensus engines to go-ethereum. In short, it
introduces a generic consensus interface, and refactors the entire codebase to
use this interface.
