Background task manager (#332)

- [x] New background worker trait
- [x] Adapt all current workers to use new API
- [x] Command to list currently running workers, and whether they are active, idle, or dead
- [x] Error reporting
- Optimizations
  - [x] Merkle updater: several items per iteration
  - [ ] Use `tokio::task::spawn_blocking` where appropriate so that CPU-intensive tasks don't block other things going on
- scrub:
  - [x] have only one worker with a channel to start/pause/cancel
  - [x] automatic scrub
  - [x] ability to view and change tranquility from CLI
  - [x] persistence of a few info
- [ ] Testing

Co-authored-by: Alex Auvolat <alex@adnab.me>
Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/332
Co-authored-by: Alex <alex@adnab.me>
Co-committed-by: Alex <alex@adnab.me>

1 files changed, 58 insertions, 0 deletions

diff --git a/src/garage/cli/util.rs b/src/garage/cli/util.rs
index 329e8a3e..396938ae 100644
--- a/src/garage/cli/util.rs
+++ b/src/garage/cli/util.rs
@@ -1,14 +1,19 @@
 use std::collections::HashMap;
+use std::time::Duration;
 
+use garage_util::background::*;
 use garage_util::crdt::*;
 use garage_util::data::Uuid;
 use garage_util::error::*;
 use garage_util::formater::format_table;
+use garage_util::time::*;
 
 use garage_model::bucket_table::*;
 use garage_model::key_table::*;
 use garage_model::s3::object_table::{BYTES, OBJECTS, UNFINISHED_UPLOADS};
 
+use crate::cli::structs::WorkerListOpt;
+
 pub fn print_bucket_list(bl: Vec<Bucket>) {
 	println!("List of buckets:");
 
@@ -235,3 +240,56 @@ pub fn find_matching_node(
 		Ok(candidates[0])
 	}
 }
+
+pub fn print_worker_info(wi: HashMap<usize, WorkerInfo>, wlo: WorkerListOpt) {
+	let mut wi = wi.into_iter().collect::<Vec<_>>();
+	wi.sort_by_key(|(tid, info)| {
+		(
+			match info.state {
+				WorkerState::Busy | WorkerState::Throttled(_) => 0,
+				WorkerState::Idle => 1,
+				WorkerState::Done => 2,
+			},
+			*tid,
+		)
+	});
+
+	let mut table = vec![];
+	for (tid, info) in wi.iter() {
+		if wlo.busy && !matches!(info.state, WorkerState::Busy | WorkerState::Throttled(_)) {
+			continue;
+		}
+		if wlo.errors && info.errors == 0 {
+			continue;
+		}
+
+		table.push(format!("{}\t{}\t{}", tid, info.state, info.name));
+		if let Some(i) = &info.info {
+			table.push(format!("\t\t  {}", i));
+		}
+		let tf = timeago::Formatter::new();
+		let (err_ago, err_msg) = info
+			.last_error
+			.as_ref()
+			.map(|(m, t)| {
+				(
+					tf.convert(Duration::from_millis(now_msec() - t)),
+					m.as_str(),
+				)
+			})
+			.unwrap_or(("(?) ago".into(), "(?)"));
+		if info.consecutive_errors > 0 {
+			table.push(format!(
+				"\t\t  {} consecutive errors ({} total), last {}",
+				info.consecutive_errors, info.errors, err_ago,
+			));
+			table.push(format!("\t\t  {}", err_msg));
+		} else if info.errors > 0 {
+			table.push(format!("\t\t  ({} errors, last {})", info.errors, err_ago,));
+			if wlo.errors {
+				table.push(format!("\t\t  {}", err_msg));
+			}
+		}
+	}
+	format_table(table);
+}