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mod snapshot_gossip_manager;
use {
agave_snapshots::{
SnapshotKind, paths as snapshot_paths, snapshot_config::SnapshotConfig,
snapshot_hash::StartingSnapshotHashes,
},
snapshot_gossip_manager::SnapshotGossipManager,
solana_accounts_db::account_storage_entry::AccountStorageEntry,
solana_clock::Slot,
solana_gossip::cluster_info::ClusterInfo,
solana_measure::{meas_dur, measure::Measure, measure_us},
solana_perf::thread::renice_this_thread,
solana_runtime::{
accounts_background_service::PendingSnapshotPackages,
snapshot_controller::SnapshotController,
snapshot_package::{BankSnapshotPackage, SnapshotPackage},
snapshot_utils,
},
std::{
sync::{
Arc, Mutex,
atomic::{AtomicBool, Ordering},
},
thread::{self, Builder, JoinHandle},
time::{Duration, Instant},
},
};
pub struct SnapshotPackagerService {
t_snapshot_packager: JoinHandle<()>,
}
impl SnapshotPackagerService {
pub const NAME: &str = "SnapshotPackagerService";
/// If there are no snapshot packages to handle, limit how often we re-check
const LOOP_LIMITER: Duration = Duration::from_millis(100);
pub fn new(
pending_snapshot_packages: Arc<Mutex<PendingSnapshotPackages>>,
starting_snapshot_hashes: Option<StartingSnapshotHashes>,
exit: Arc<AtomicBool>,
exit_backpressure: Option<Arc<AtomicBool>>,
cluster_info: Arc<ClusterInfo>,
snapshot_controller: Arc<SnapshotController>,
enable_gossip_push: bool,
niceness_adj: i8,
) -> Self {
let t_snapshot_packager = Builder::new()
.name("solSnapshotPkgr".to_string())
.spawn(move || {
if let Some(exit_backpressure) = &exit_backpressure {
exit_backpressure.store(true, Ordering::Relaxed);
}
info!("{} has started", Self::NAME);
let snapshot_config = snapshot_controller.snapshot_config();
renice_this_thread(niceness_adj).unwrap();
let mut snapshot_gossip_manager = enable_gossip_push
.then(|| SnapshotGossipManager::new(cluster_info, starting_snapshot_hashes));
let mut teardown_state = None;
loop {
if exit.load(Ordering::Relaxed) {
if let Some(teardown_state) = teardown_state {
info!("Received exit request, tearing down...");
let (_, dur) = meas_dur!(Self::teardown(
teardown_state,
snapshot_controller.snapshot_config(),
));
info!("Teardown completed in {dur:?}.");
}
break;
}
let Some(snapshot_package) =
Self::get_next_snapshot_package(&pending_snapshot_packages)
else {
std::thread::sleep(Self::LOOP_LIMITER);
continue;
};
info!("handling snapshot package: {snapshot_package:?}");
let enqueued_time = snapshot_package.enqueued.elapsed();
let measure_handling = Measure::start("");
let snapshot_kind = snapshot_package.snapshot_kind;
let snapshot_slot = snapshot_package.slot;
let snapshot_hash = snapshot_package.hash;
snapshot_controller.set_latest_bank_snapshot_slot(snapshot_slot);
if exit_backpressure.is_some() {
// With exit backpressure, we will delay flushing snapshot storages
// until we receive a graceful exit request.
// Save the snapshot storages here, so we can flush later (as needed).
// For fastboot snapshot packages, the bank snapshot is saved and
// the rest of the snapshotting process is skipped
if snapshot_kind == SnapshotKind::Fastboot {
teardown_state = Some(TeardownState {
snapshot_slot: snapshot_package.slot,
snapshot_storages: snapshot_package.snapshot_storages.clone(),
bank_snapshot_package: Some(snapshot_package.bank_snapshot_package),
});
let handling_time = measure_handling.end_as_us();
datapoint_info!(
"snapshot_packager_service",
("enqueued_time_us", enqueued_time.as_micros(), i64),
("handling_time_us", handling_time, i64),
);
continue;
} else {
teardown_state = Some(TeardownState {
snapshot_slot: snapshot_package.slot,
snapshot_storages: snapshot_package.snapshot_storages.clone(),
bank_snapshot_package: None,
});
}
}
let archive_time = Instant::now();
// Serializing the snapshot package is not allowed to fail, as archiving is
// not allowed to fail (see comment on archive_snapshot_package below
let bank_snapshot_info = snapshot_utils::serialize_snapshot(
&snapshot_config.bank_snapshots_dir,
snapshot_config.snapshot_version,
snapshot_package.bank_snapshot_package,
snapshot_package.snapshot_storages.as_slice(),
exit_backpressure.is_none(),
);
let Ok(bank_snapshot_info) = bank_snapshot_info else {
let err = bank_snapshot_info.unwrap_err();
error!(
"Stopping {}! Fatal error while serializing snapshot for slot \
{snapshot_slot}: {err}",
Self::NAME,
);
exit.store(true, Ordering::Relaxed);
break;
};
if let SnapshotKind::Archive(snapshot_archive_kind) = snapshot_kind {
// Archiving the snapshot package is not allowed to fail.
// AccountsBackgroundService calls `clean_accounts()` with a value for
// latest_full_snapshot_slot that requires this archive call to succeed.
if let Err(err) = snapshot_utils::archive_snapshot_package(
snapshot_archive_kind,
snapshot_slot,
snapshot_hash,
&bank_snapshot_info.snapshot_dir,
snapshot_package.snapshot_storages,
snapshot_config,
) {
error!(
"Stopping {}! Fatal error while archiving snapshot package: {err}",
Self::NAME,
);
exit.store(true, Ordering::Relaxed);
break;
}
}
let archive_time_us = archive_time.elapsed().as_micros();
if let Some(snapshot_gossip_manager) = snapshot_gossip_manager.as_mut() {
snapshot_gossip_manager
.push_snapshot_hash(snapshot_kind, (snapshot_slot, snapshot_hash));
}
let (_, purge_archives_time_us) =
measure_us!(snapshot_utils::purge_old_snapshot_archives(
&snapshot_config.full_snapshot_archives_dir,
&snapshot_config.incremental_snapshot_archives_dir,
snapshot_config.maximum_full_snapshot_archives_to_retain,
snapshot_config.maximum_incremental_snapshot_archives_to_retain,
));
// Now that this snapshot package has been archived, it is safe to remove
// all bank snapshots older than this slot. We want to keep the bank
// snapshot *at this slot* so that it can be used during restarts, when
// booting from local state.
let (_, purge_bank_snapshots_time_us) =
measure_us!(snapshot_utils::purge_bank_snapshots_older_than_slot(
&snapshot_config.bank_snapshots_dir,
snapshot_slot,
));
let handling_time_us = measure_handling.end_as_us();
datapoint_info!(
"snapshot_packager_service",
("enqueued_time_us", enqueued_time.as_micros(), i64),
("handling_time_us", handling_time_us, i64),
("archive_time_us", archive_time_us, i64),
(
"purge_old_snapshots_time_us",
purge_bank_snapshots_time_us,
i64
),
("purge_old_archives_time_us", purge_archives_time_us, i64),
);
}
info!("{} has stopped", Self::NAME);
if let Some(exit_backpressure) = &exit_backpressure {
exit_backpressure.store(false, Ordering::Relaxed);
}
})
.unwrap();
Self {
t_snapshot_packager,
}
}
pub fn join(self) -> thread::Result<()> {
self.t_snapshot_packager.join()
}
/// Returns the next snapshot package to handle
fn get_next_snapshot_package(
pending_snapshot_packages: &Mutex<PendingSnapshotPackages>,
) -> Option<SnapshotPackage> {
pending_snapshot_packages.lock().unwrap().pop()
}
/// Performs final operations before gracefully shutting down
fn teardown(state: TeardownState, snapshot_config: &SnapshotConfig) {
let TeardownState {
snapshot_slot,
snapshot_storages,
bank_snapshot_package,
} = state;
if let Some(bank_snapshot_package) = bank_snapshot_package {
info!("Serializing bank snapshot...");
let start = Instant::now();
let result = snapshot_utils::serialize_snapshot(
&snapshot_config.bank_snapshots_dir,
snapshot_config.snapshot_version,
bank_snapshot_package,
snapshot_storages.as_slice(),
false,
);
if let Err(err) = result {
warn!(
"Failed to serialize bank '{}': {err}",
snapshot_config.bank_snapshots_dir.as_path().display(),
);
// If serializing the bank fails, we do *NOT* want to write
// the mark_bank_snapshot_as_loadable file, so return early.
return;
}
info!("Serializing bank snapshot... Done in {:?}", start.elapsed());
}
info!("Flushing account storages...");
let start = Instant::now();
for storage in &snapshot_storages {
let result = storage.flush();
if let Err(err) = result {
warn!(
"Failed to flush account storage '{}': {err}",
storage.path().display(),
);
// If flushing a storage failed, we do *NOT* want to write
// the "storages flushed" file, so return early.
return;
}
}
info!("Flushing account storages... Done in {:?}", start.elapsed());
let bank_snapshot_dir = snapshot_paths::get_bank_snapshot_dir(
&snapshot_config.bank_snapshots_dir,
snapshot_slot,
);
info!("Hard linking account storages...");
let start = Instant::now();
let result = snapshot_utils::hard_link_storages_to_snapshot(
&bank_snapshot_dir,
snapshot_slot,
&snapshot_storages,
);
if let Err(err) = result {
warn!("Failed to hard link account storages: {err}");
// If hard linking the storages failed, we do *NOT* want to mark the bank snapshot as
// loadable so return early.
return;
}
info!(
"Hard linking account storages... Done in {:?}",
start.elapsed(),
);
info!("Saving obsolete accounts...");
let start = Instant::now();
let result = snapshot_utils::write_obsolete_accounts_to_snapshot(
&bank_snapshot_dir,
&snapshot_storages,
snapshot_slot,
);
if let Err(err) = result {
warn!("Failed to serialize obsolete accounts: {err}");
// If serializing the obsolete accounts failed, we do *NOT* want to mark the bank snapshot
// as loadable so return early.
return;
}
info!("Saving obsolete accounts... Done in {:?}", start.elapsed());
let result = snapshot_utils::mark_bank_snapshot_as_loadable(&bank_snapshot_dir);
if let Err(err) = result {
warn!("Failed to mark bank snapshot as loadable: {err}");
}
}
}
/// The state required to run `teardown()`
// Note, don't derive Debug, because we don't want to print out 432k+ `AccountStorageEntry`s...
struct TeardownState {
/// The slot of the latest snapshot
snapshot_slot: Slot,
/// The storages of the latest snapshot
snapshot_storages: Vec<Arc<AccountStorageEntry>>,
/// For fastboot snapshots archiving is not required so serialization of the bank snapshot
/// can be deferred until teardown. In this case `bank_snapshot_package` will be `Some` and
/// during teardown the bank snapshot will be serialized to storage. For other snapshot types
/// `bank_snapshot_package` will be `None` because the serialization would have already occurred
/// when the snapshot archive was written.
bank_snapshot_package: Option<BankSnapshotPackage>,
}