From 791120c0c1ac66186a5a1b05cc525d94d19ea5f3 Mon Sep 17 00:00:00 2001
From: Donald Guy <donaldguy@hey.com>
Date: Tue, 4 May 2021 18:49:13 -0400
Subject: [PATCH 1/3] threads1: use more threads, model more reference counting
- Switch from a single additional thread (receiving/holding a single `Arc::clone` reference) running a loop modeling 10 sequential jobs, to a loop generating 10 threads each modeling 1 job (each getting their own `Arc::clone` reference)
- use the previously ignored `for` loop var to keep the execution timing approx the same
- Print a more descriptive waiting message (taking an opportunity to use comment to disambiguate the count)
---
exercises/threads/threads1.rs | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/exercises/threads/threads1.rs b/exercises/threads/threads1.rs
index f31b317..4bf6aa3 100644
--- a/exercises/threads/threads1.rs
+++ b/exercises/threads/threads1.rs
@@ -1,10 +1,7 @@
// threads1.rs
// Make this compile! Execute `rustlings hint threads1` for hints :)
-// The idea is the thread spawned on line 22 is completing jobs while the main thread is
-// monitoring progress until 10 jobs are completed. Because of the difference between the
-// spawned threads' sleep time, and the waiting threads sleep time, when you see 6 lines
-// of "waiting..." and the program ends without timing out when running,
-// you've got it :)
+// The idea is the threads spawned on line 22 are completing jobs while the main thread is
+// monitoring progress until 10 jobs are completed.
// I AM NOT DONE
@@ -18,15 +15,18 @@ struct JobStatus {
fn main() {
let status = Arc::new(JobStatus { jobs_completed: 0 });
- let status_shared = status.clone();
- thread::spawn(move || {
- for _ in 0..10 {
- thread::sleep(Duration::from_millis(250));
- status_shared.jobs_completed += 1;
- }
- });
+ for i in 0..10 {
+ let status_ref = Arc::clone(&status);
+ thread::spawn(move || {
+ thread::sleep(Duration::from_millis(250 * i));
+ status_ref.jobs_completed += 1;
+ });
+ }
while status.jobs_completed < 10 {
- println!("waiting... ");
+ println!("waiting for {} jobs ({} jobs running)... ",
+ (10 - status.jobs_completed),
+ (Arc::strong_count(&status) - 1) // subtract one for refrence in _this_ thread
+ );
thread::sleep(Duration::from_millis(500));
}
}
From 1cd661997c9773ea0d7fca440a3b5a27012a2905 Mon Sep 17 00:00:00 2001
From: Donald Guy <donaldguy@hey.com>
Date: Tue, 4 May 2021 21:25:48 -0400
Subject: [PATCH 2/3] Fix referenced line number
---
exercises/threads/threads1.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/exercises/threads/threads1.rs b/exercises/threads/threads1.rs
index 4bf6aa3..6fa4b19 100644
--- a/exercises/threads/threads1.rs
+++ b/exercises/threads/threads1.rs
@@ -1,6 +1,6 @@
// threads1.rs
// Make this compile! Execute `rustlings hint threads1` for hints :)
-// The idea is the threads spawned on line 22 are completing jobs while the main thread is
+// The idea is the threads spawned on line 20 are completing jobs while the main thread is
// monitoring progress until 10 jobs are completed.
// I AM NOT DONE
From e696f987cd09e47b40f5b02fa74eed17f54ea8b8 Mon Sep 17 00:00:00 2001
From: Donald Guy <donaldguy@hey.com>
Date: Tue, 4 May 2021 21:38:18 -0400
Subject: [PATCH 3/3] Avoid first thread sleeping 0 millis
---
exercises/threads/threads1.rs | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/exercises/threads/threads1.rs b/exercises/threads/threads1.rs
index 6fa4b19..d86cb3c 100644
--- a/exercises/threads/threads1.rs
+++ b/exercises/threads/threads1.rs
@@ -15,7 +15,7 @@ struct JobStatus {
fn main() {
let status = Arc::new(JobStatus { jobs_completed: 0 });
- for i in 0..10 {
+ for i in 1..=10 {
let status_ref = Arc::clone(&status);
thread::spawn(move || {
thread::sleep(Duration::from_millis(250 * i));