zebra/zebrad/src/components/sync/progress.rs

347 lines
14 KiB
Rust

//! Progress tracking for blockchain syncing.
use std::{
cmp::min,
ops::Add,
time::{Duration, Instant},
};
use chrono::Utc;
use num_integer::div_ceil;
use zebra_chain::{
block::{Height, HeightDiff},
chain_sync_status::ChainSyncStatus,
chain_tip::ChainTip,
fmt::humantime_seconds,
parameters::{Network, NetworkUpgrade, POST_BLOSSOM_POW_TARGET_SPACING},
};
use zebra_consensus::ParameterCheckpoint as _;
use zebra_state::MAX_BLOCK_REORG_HEIGHT;
use crate::components::sync::SyncStatus;
/// The amount of time between progress logs.
const LOG_INTERVAL: Duration = Duration::from_secs(60);
/// The amount of time between progress bar updates.
const PROGRESS_BAR_INTERVAL: Duration = Duration::from_secs(5);
/// The number of blocks we consider to be close to the tip.
///
/// Most chain forks are 1-7 blocks long.
const MAX_CLOSE_TO_TIP_BLOCKS: HeightDiff = 1;
/// Skip slow sync warnings when we are this close to the tip.
///
/// In testing, we've seen warnings around 30 blocks.
///
/// TODO: replace with `MAX_CLOSE_TO_TIP_BLOCKS` after fixing slow syncing near tip (#3375)
const MIN_SYNC_WARNING_BLOCKS: HeightDiff = 60;
/// The number of fractional digits in sync percentages.
const SYNC_PERCENT_FRAC_DIGITS: usize = 3;
/// The minimum number of extra blocks mined between updating a checkpoint list,
/// and running an automated test that depends on that list.
///
/// Makes sure that the block finalization code always runs in sync tests,
/// even if the miner or test node clock is wrong by a few minutes.
///
/// This is an estimate based on the time it takes to:
/// - get the tip height from `zcashd`,
/// - run `zebra-checkpoints` to update the checkpoint list,
/// - submit a pull request, and
/// - run a CI test that logs progress based on the new checkpoint height.
///
/// We might add tests that sync from a cached tip state,
/// so we only allow a few extra blocks here.
//
// TODO: change to HeightDiff?
const MIN_BLOCKS_MINED_AFTER_CHECKPOINT_UPDATE: u32 = 10;
/// Logs Zebra's estimated progress towards the chain tip every minute or so, and
/// updates a terminal progress bar every few seconds.
///
/// TODO:
/// - log progress towards, remaining blocks before, and remaining time to next network upgrade
/// - add some progress info to the metrics
pub async fn show_block_chain_progress(
network: Network,
latest_chain_tip: impl ChainTip,
sync_status: SyncStatus,
) -> ! {
// The minimum number of extra blocks after the highest checkpoint, based on:
// - the non-finalized state limit, and
// - the minimum number of extra blocks mined between a checkpoint update,
// and the automated tests for that update.
let min_after_checkpoint_blocks =
MAX_BLOCK_REORG_HEIGHT + MIN_BLOCKS_MINED_AFTER_CHECKPOINT_UPDATE;
let min_after_checkpoint_blocks: HeightDiff = min_after_checkpoint_blocks.into();
// The minimum height of the valid best chain, based on:
// - the hard-coded checkpoint height,
// - the minimum number of blocks after the highest checkpoint.
let after_checkpoint_height = network
.checkpoint_list()
.max_height()
.add(min_after_checkpoint_blocks)
.expect("hard-coded checkpoint height is far below Height::MAX");
let target_block_spacing = NetworkUpgrade::target_spacing_for_height(network, Height::MAX);
let max_block_spacing =
NetworkUpgrade::minimum_difficulty_spacing_for_height(network, Height::MAX);
// We expect the state height to increase at least once in this interval.
//
// Most chain forks are 1-7 blocks long.
//
// TODO: remove the target_block_spacing multiplier,
// after fixing slow syncing near tip (#3375)
let min_state_block_interval = max_block_spacing.unwrap_or(target_block_spacing * 4) * 2;
// Formatted strings for logging.
let target_block_spacing = humantime_seconds(
target_block_spacing
.to_std()
.expect("constant fits in std::Duration"),
);
let max_block_spacing = max_block_spacing
.map(|duration| {
humantime_seconds(duration.to_std().expect("constant fits in std::Duration"))
})
.unwrap_or_else(|| "None".to_string());
// The last time we downloaded and verified at least one block.
//
// Initialized to the start time to simplify the code.
let mut last_state_change_time = Utc::now();
// The state tip height, when we last downloaded and verified at least one block.
//
// Initialized to the genesis height to simplify the code.
let mut last_state_change_height = Height(0);
// The last time we logged an update.
let mut last_log_time = Instant::now();
#[cfg(feature = "progress-bar")]
let block_bar = howudoin::new().label("Blocks");
loop {
let now = Utc::now();
let instant_now = Instant::now();
let is_syncer_stopped = sync_status.is_close_to_tip();
if let Some(estimated_height) =
latest_chain_tip.estimate_network_chain_tip_height(network, now)
{
// The estimate/actual race doesn't matter here,
// because we're only using it for metrics and logging.
let current_height = latest_chain_tip
.best_tip_height()
.expect("unexpected empty state: estimate requires a block height");
let network_upgrade = NetworkUpgrade::current(network, current_height);
// Send progress reports for block height
//
// TODO: split the progress bar height update into its own function.
#[cfg(feature = "progress-bar")]
if matches!(howudoin::cancelled(), Some(true)) {
block_bar.close();
} else {
block_bar
.set_pos(current_height.0)
.set_len(u64::from(estimated_height.0));
}
// Skip logging and status updates if it isn't time for them yet.
let elapsed_since_log = instant_now.saturating_duration_since(last_log_time);
if elapsed_since_log < LOG_INTERVAL {
tokio::time::sleep(PROGRESS_BAR_INTERVAL).await;
continue;
} else {
last_log_time = instant_now;
}
// TODO: split logging / status updates into their own function.
// Work out the sync progress towards the estimated tip.
let sync_progress = f64::from(current_height.0) / f64::from(estimated_height.0);
let sync_percent = format!(
"{:.frac$}%",
sync_progress * 100.0,
frac = SYNC_PERCENT_FRAC_DIGITS,
);
let mut remaining_sync_blocks = estimated_height - current_height;
if remaining_sync_blocks < 0 {
remaining_sync_blocks = 0;
}
// Work out how long it has been since the state height has increased.
//
// Non-finalized forks can decrease the height, we only want to track increases.
if current_height > last_state_change_height {
last_state_change_height = current_height;
last_state_change_time = now;
}
let time_since_last_state_block_chrono =
now.signed_duration_since(last_state_change_time);
let time_since_last_state_block = humantime_seconds(
time_since_last_state_block_chrono
.to_std()
.unwrap_or_default(),
);
if time_since_last_state_block_chrono > min_state_block_interval {
// The state tip height hasn't increased for a long time.
//
// Block verification can fail if the local node's clock is wrong.
warn!(
%sync_percent,
?current_height,
?network_upgrade,
%time_since_last_state_block,
%target_block_spacing,
%max_block_spacing,
?is_syncer_stopped,
"chain updates have stalled, \
state height has not increased for {} minutes. \
Hint: check your network connection, \
and your computer clock and time zone",
time_since_last_state_block_chrono.num_minutes(),
);
// TODO: use add_warn(), but only add each warning once
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: sync has stalled", network_upgrade));
} else if is_syncer_stopped && remaining_sync_blocks > MIN_SYNC_WARNING_BLOCKS {
// We've stopped syncing blocks, but we estimate we're a long way from the tip.
//
// TODO: warn after fixing slow syncing near tip (#3375)
info!(
%sync_percent,
?current_height,
?network_upgrade,
?remaining_sync_blocks,
?after_checkpoint_height,
%time_since_last_state_block,
"initial sync is very slow, or estimated tip is wrong. \
Hint: check your network connection, \
and your computer clock and time zone",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!(
"{}: sync is very slow, or estimated tip is wrong",
network_upgrade
));
} else if is_syncer_stopped && current_height <= after_checkpoint_height {
// We've stopped syncing blocks,
// but we're below the minimum height estimated from our checkpoints.
let min_minutes_after_checkpoint_update = div_ceil(
MIN_BLOCKS_MINED_AFTER_CHECKPOINT_UPDATE * POST_BLOSSOM_POW_TARGET_SPACING,
60,
);
warn!(
%sync_percent,
?current_height,
?network_upgrade,
?remaining_sync_blocks,
?after_checkpoint_height,
%time_since_last_state_block,
"initial sync is very slow, and state is below the highest checkpoint. \
Hint: check your network connection, \
and your computer clock and time zone. \
Dev Hint: were the checkpoints updated in the last {} minutes?",
min_minutes_after_checkpoint_update,
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: sync is very slow", network_upgrade));
} else if is_syncer_stopped {
// We've stayed near the tip for a while, and we've stopped syncing lots of blocks.
// So we're mostly using gossiped blocks now.
info!(
%sync_percent,
?current_height,
?network_upgrade,
?remaining_sync_blocks,
%time_since_last_state_block,
"finished initial sync to chain tip, using gossiped blocks",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: waiting for next block", network_upgrade));
} else if remaining_sync_blocks <= MAX_CLOSE_TO_TIP_BLOCKS {
// We estimate we're near the tip, but we have been syncing lots of blocks recently.
// We might also be using some gossiped blocks.
info!(
%sync_percent,
?current_height,
?network_upgrade,
?remaining_sync_blocks,
%time_since_last_state_block,
"close to finishing initial sync, \
confirming using syncer and gossiped blocks",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: finishing initial sync", network_upgrade));
} else {
// We estimate we're far from the tip, and we've been syncing lots of blocks.
info!(
%sync_percent,
?current_height,
?network_upgrade,
?remaining_sync_blocks,
%time_since_last_state_block,
"estimated progress to chain tip",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: syncing blocks", network_upgrade));
}
} else {
let sync_percent = format!("{:.SYNC_PERCENT_FRAC_DIGITS$} %", 0.0f64,);
#[cfg(feature = "progress-bar")]
let network_upgrade = NetworkUpgrade::Genesis;
if is_syncer_stopped {
// We've stopped syncing blocks,
// but we haven't downloaded and verified the genesis block.
warn!(
%sync_percent,
current_height = %"None",
"initial sync can't download and verify the genesis block. \
Hint: check your network connection, \
and your computer clock and time zone",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!("{}: can't download genesis block", network_upgrade));
} else {
// We're waiting for the genesis block to be committed to the state,
// before we can estimate the best chain tip.
info!(
%sync_percent,
current_height = %"None",
"initial sync is waiting to download the genesis block",
);
#[cfg(feature = "progress-bar")]
block_bar.desc(format!(
"{}: waiting to download genesis block",
network_upgrade
));
}
}
tokio::time::sleep(min(LOG_INTERVAL, PROGRESS_BAR_INTERVAL)).await;
}
}