mirror of
https://github.com/tendermint/tendermint.git
synced 2026-02-04 11:02:06 +00:00
1069ffc6aa
This is largely a cherry pick of #6755 with some additional fixups added where detected. This change moves the blockchain package to a package called blocksync. Additionally, it renames the relevant uses of the term `fastsync` to `blocksync`. closes: #9227 #### PR checklist - [ ] Tests written/updated, or no tests needed - [x] `CHANGELOG_PENDING.md` updated, or no changelog entry needed - [x] Updated relevant documentation (`docs/`) and code comments, or no documentation updates needed
52 lines
2.0 KiB
Markdown
52 lines
2.0 KiB
Markdown
---
|
|
order: 10
|
|
---
|
|
|
|
# Block Sync
|
|
*Formerly known as Fast Sync*
|
|
|
|
In a proof of work blockchain, syncing with the chain is the same
|
|
process as staying up-to-date with the consensus: download blocks, and
|
|
look for the one with the most total work. In proof-of-stake, the
|
|
consensus process is more complex, as it involves rounds of
|
|
communication between the nodes to determine what block should be
|
|
committed next. Using this process to sync up with the blockchain from
|
|
scratch can take a very long time. It's much faster to just download
|
|
blocks and check the merkle tree of validators than to run the real-time
|
|
consensus gossip protocol.
|
|
|
|
## Using Block Sync
|
|
|
|
To support faster syncing, Tendermint offers a `block-sync` mode, which
|
|
is enabled by default, and can be toggled in the `config.toml` or via
|
|
`--block_sync=false`.
|
|
|
|
In this mode, the Tendermint daemon will sync hundreds of times faster
|
|
than if it used the real-time consensus process. Once caught up, the
|
|
daemon will switch out of Block Sync and into the normal consensus mode.
|
|
After running for some time, the node is considered `caught up` if it
|
|
has at least one peer and it's height is at least as high as the max
|
|
reported peer height. See [the IsCaughtUp
|
|
method](https://github.com/tendermint/tendermint/blob/b467515719e686e4678e6da4e102f32a491b85a0/blockchain/pool.go#L128).
|
|
|
|
Note: While there have historically been multiple versions of blocksync, v0, v1, and v2, all versions
|
|
other than v0 have been deprecated in favor of the simplest and most well understood algorithm.
|
|
|
|
```toml
|
|
#######################################################
|
|
### Block Sync Configuration Options ###
|
|
#######################################################
|
|
[blocksync]
|
|
|
|
# Block Sync version to use:
|
|
#
|
|
# In v0.37, v1 and v2 of the block sync protocols were deprecated.
|
|
# Please use v0 instead.
|
|
#
|
|
# 1) "v0" - the default block sync implementation
|
|
version = "v0"
|
|
```
|
|
|
|
If we're lagging sufficiently, we should go back to block syncing, but
|
|
this is an [open issue](https://github.com/tendermint/tendermint/issues/129).
|