This PR implements the following modifications
- Don't shortcut check if block is present, thus avoid disk lookup
- Don't check hash ancestry in early-check (it's still done in parallel checker)
- Don't check time.Now for every single header
Charts and background info can be found here: https://github.com/holiman/headerimport/blob/main/README.md
With these changes, writing 1M headers goes down to from 80s to 62s.
* core, eth: some fixes for freezer
* vendor, core/rawdb, cmd/geth: add db inspector
* core, cmd/utils: check ancient store path forceily
* cmd/geth, common, core/rawdb: a few fixes
* cmd/geth: support windows file rename and fix rename error
* core: support ancient plugin
* core, cmd: streaming file copy
* cmd, consensus, core, tests: keep genesis in leveldb
* core: write txlookup during ancient init
* core: bump database version
* all: freezer style syncing
core, eth, les, light: clean up freezer relative APIs
core, eth, les, trie, ethdb, light: clean a bit
core, eth, les, light: add unit tests
core, light: rewrite setHead function
core, eth: fix downloader unit tests
core: add receipt chain insertion test
core: use constant instead of hardcoding table name
core: fix rollback
core: fix setHead
core/rawdb: remove canonical block first and then iterate side chain
core/rawdb, ethdb: add hasAncient interface
eth/downloader: calculate ancient limit via cht first
core, eth, ethdb: lots of fixes
* eth/downloader: print ancient disable log only for fast sync
