From f3f27293df83986ba29fb03f8af26a2177518e20 Mon Sep 17 00:00:00 2001 From: Alex Auvolat Date: Wed, 4 Jan 2023 13:07:13 +0100 Subject: Uniform framework for bg variable management --- src/block/resync.rs | 108 ++++++++++++++++++++++++++++------------------------ 1 file changed, 58 insertions(+), 50 deletions(-) (limited to 'src/block/resync.rs') diff --git a/src/block/resync.rs b/src/block/resync.rs index 9c7b3b0e..ea280ad4 100644 --- a/src/block/resync.rs +++ b/src/block/resync.rs @@ -3,7 +3,6 @@ use std::convert::TryInto; use std::sync::{Arc, Mutex}; use std::time::Duration; -use arc_swap::ArcSwap; use async_trait::async_trait; use serde::{Deserialize, Serialize}; @@ -22,7 +21,7 @@ use garage_util::background::*; use garage_util::data::*; use garage_util::error::*; use garage_util::metrics::RecordDuration; -use garage_util::persister::Persister; +use garage_util::persister::PersisterShared; use garage_util::time::*; use garage_util::tranquilizer::Tranquilizer; @@ -49,13 +48,12 @@ const INITIAL_RESYNC_TRANQUILITY: u32 = 2; pub struct BlockResyncManager { pub(crate) queue: CountedTree, - pub(crate) notify: Notify, + pub(crate) notify: Arc, pub(crate) errors: CountedTree, busy_set: BusySet, - persister: Persister, - persisted: ArcSwap, + persister: PersisterShared, } #[derive(Serialize, Deserialize, Clone, Copy)] @@ -64,6 +62,14 @@ struct ResyncPersistedConfig { tranquility: u32, } impl garage_util::migrate::InitialFormat for ResyncPersistedConfig {} +impl Default for ResyncPersistedConfig { + fn default() -> Self { + ResyncPersistedConfig { + n_workers: 1, + tranquility: INITIAL_RESYNC_TRANQUILITY, + } + } +} enum ResyncIterResult { BusyDidSomething, @@ -91,22 +97,14 @@ impl BlockResyncManager { .expect("Unable to open block_local_resync_errors tree"); let errors = CountedTree::new(errors).expect("Could not count block_local_resync_errors"); - let persister = Persister::new(&system.metadata_dir, "resync_cfg"); - let persisted = match persister.load() { - Ok(v) => v, - Err(_) => ResyncPersistedConfig { - n_workers: 1, - tranquility: INITIAL_RESYNC_TRANQUILITY, - }, - }; + let persister = PersisterShared::new(&system.metadata_dir, "resync_cfg"); Self { queue, - notify: Notify::new(), + notify: Arc::new(Notify::new()), errors, busy_set: Arc::new(Mutex::new(HashSet::new())), persister, - persisted: ArcSwap::new(Arc::new(persisted)), } } @@ -142,6 +140,38 @@ impl BlockResyncManager { ))) } + pub fn register_bg_vars(&self, vars: &mut vars::BgVars) { + let notify = self.notify.clone(); + vars.register_rw( + &self.persister, + "resync-worker-count", + |p| p.get_with(|x| x.n_workers), + move |p, n_workers| { + if !(1..=MAX_RESYNC_WORKERS).contains(&n_workers) { + return Err(Error::Message(format!( + "Invalid number of resync workers, must be between 1 and {}", + MAX_RESYNC_WORKERS + ))); + } + p.set_with(|x| x.n_workers = n_workers)?; + notify.notify_waiters(); + Ok(()) + }, + ); + + let notify = self.notify.clone(); + vars.register_rw( + &self.persister, + "resync-tranquility", + |p| p.get_with(|x| x.tranquility), + move |p, tranquility| { + p.set_with(|x| x.tranquility = tranquility)?; + notify.notify_waiters(); + Ok(()) + }, + ); + } + // ---- Resync loop ---- // This part manages a queue of blocks that need to be @@ -436,33 +466,6 @@ impl BlockResyncManager { Ok(()) } - - async fn update_persisted( - &self, - update: impl Fn(&mut ResyncPersistedConfig), - ) -> Result<(), Error> { - let mut cfg: ResyncPersistedConfig = *self.persisted.load().as_ref(); - update(&mut cfg); - self.persister.save_async(&cfg).await?; - self.persisted.store(Arc::new(cfg)); - self.notify.notify_waiters(); - Ok(()) - } - - pub async fn set_n_workers(&self, n_workers: usize) -> Result<(), Error> { - if !(1..=MAX_RESYNC_WORKERS).contains(&n_workers) { - return Err(Error::Message(format!( - "Invalid number of resync workers, must be between 1 and {}", - MAX_RESYNC_WORKERS - ))); - } - self.update_persisted(|cfg| cfg.n_workers = n_workers).await - } - - pub async fn set_tranquility(&self, tranquility: u32) -> Result<(), Error> { - self.update_persisted(|cfg| cfg.tranquility = tranquility) - .await - } } impl Drop for BusyBlock { @@ -477,15 +480,18 @@ pub(crate) struct ResyncWorker { manager: Arc, tranquilizer: Tranquilizer, next_delay: Duration, + persister: PersisterShared, } impl ResyncWorker { pub(crate) fn new(index: usize, manager: Arc) -> Self { + let persister = manager.resync.persister.clone(); Self { index, manager, tranquilizer: Tranquilizer::new(30), next_delay: Duration::from_secs(10), + persister, } } } @@ -497,9 +503,9 @@ impl Worker for ResyncWorker { } fn status(&self) -> WorkerStatus { - let persisted = self.manager.resync.persisted.load(); + let (n_workers, tranquility) = self.persister.get_with(|x| (x.n_workers, x.tranquility)); - if self.index >= persisted.n_workers { + if self.index >= n_workers { return WorkerStatus { freeform: vec!["This worker is currently disabled".into()], ..Default::default() @@ -508,22 +514,24 @@ impl Worker for ResyncWorker { WorkerStatus { queue_length: Some(self.manager.resync.queue_len().unwrap_or(0) as u64), - tranquility: Some(persisted.tranquility), + tranquility: Some(tranquility), persistent_errors: Some(self.manager.resync.errors_len().unwrap_or(0) as u64), ..Default::default() } } async fn work(&mut self, _must_exit: &mut watch::Receiver) -> Result { - if self.index >= self.manager.resync.persisted.load().n_workers { + let (n_workers, tranquility) = self.persister.get_with(|x| (x.n_workers, x.tranquility)); + + if self.index >= n_workers { return Ok(WorkerState::Idle); } self.tranquilizer.reset(); match self.manager.resync.resync_iter(&self.manager).await { - Ok(ResyncIterResult::BusyDidSomething) => Ok(self - .tranquilizer - .tranquilize_worker(self.manager.resync.persisted.load().tranquility)), + Ok(ResyncIterResult::BusyDidSomething) => { + Ok(self.tranquilizer.tranquilize_worker(tranquility)) + } Ok(ResyncIterResult::BusyDidNothing) => Ok(WorkerState::Busy), Ok(ResyncIterResult::IdleFor(delay)) => { self.next_delay = delay; @@ -542,7 +550,7 @@ impl Worker for ResyncWorker { } async fn wait_for_work(&mut self) -> WorkerState { - while self.index >= self.manager.resync.persisted.load().n_workers { + while self.index >= self.persister.get_with(|x| x.n_workers) { self.manager.resync.notify.notified().await } -- cgit v1.2.3