use arc for broadcast channels

[Victor-M-Giraldo]

closes #1199

Summary by CodeRabbit

• Refactor
  • Enhanced the transaction broadcasting mechanism for improved stability and performance.

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Walkthrough

The update involves wrapping the broadcast_tx variable in an Arc to optimize memory usage when broadcasting messages to clients in a room. This change aims to reduce the need for cloning the message for each client, thereby decreasing memory allocations and potentially improving performance.

Changes

File Path	Change Summary
.../ott-balancer/src/monolith.rs	Changed broadcast_tx type to Arc<tokio::sync::broadcast::Sender<SocketMessage>> and used Arc::new for initialization.

Assessment against linked issues

Objective	Addressed	Explanation
Use Arc for room broadcast channels (#1199)	✅	The change to wrap broadcast_tx with an Arc aligns with the objective to minimize memory cloning.

Poem

As the messages fly, swift and wide,
A clever rabbit thought to provide,
An Arc to hold them side by side,
Less cloning, more pride, in every byte!

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Review Status

Actionable comments generated: 0

Configuration used: CodeRabbit UI

Commits

Files that changed from the base of the PR and between 7b1e287 and 1400866.

Files selected for processing (1)

• crates/ott-balancer/src/monolith.rs (2 hunks)

Additional comments: 1

crates/ott-balancer/src/monolith.rs (1)

• 149-155: > Note: This review was outside the patches, so it was mapped to the patch with the greatest overlap. Original lines [152-162]

The use of Arc to wrap the broadcast_tx sender in the Room struct is consistent with the PR's objective to optimize memory usage by allowing shared ownership of the broadcast sender. This change should reduce the number of clones created when broadcasting messages to multiple clients.

However, ensure that all parts of the code that interact with broadcast_tx are updated to work with the Arc wrapped type. This includes any external modules or tests that may rely on the previous type signature.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (5d7baad) 61.5318% compared to head (190d4dc) 61.6880%.
Report is 3 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master      #1216        +/-   ##
================================================
+ Coverage   61.5318%   61.6880%   +0.1561%     
================================================
  Files           115        115                
  Lines          9322       9360        +38     
  Branches       1141       1142         +1     
================================================
+ Hits           5736       5774        +38     
  Misses         3586       3586                

☔ View full report in Codecov by Sentry.
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[Victor-M-Giraldo]

Do you know why the cypress tests fail? I took a look at the logs and it seems like they are failing to fetch the imported modules for the component tests, and it can't find a .video button for the e2e tests.

[Victor-M-Giraldo]

Also, do you know if it would it be better to use into() to change the type of broadcast_tx as opposed to using new() or does it not matter too much?

Does one use more memory as opposed to the other?

[dyc3]

Do you know why the cypress tests fail?

It's completely out of our control, and its really annoying. See cypress-io/cypress#25913

[dyc3]

I took a look at it, and the problem is that the Stream wants owned values because it has to queue them internally before they get flushed to IO. I don't think this is feasible for us right now, so we can drop this task. Sorry about that.

[Victor-M-Giraldo]

No problem. Do you think you could elaborate a little on what you mean just for my own understanding?

From what I understand stream can't take a reference to a variable. It must have ownership of msg but what does this have to do with Arc and what we were trying to do?

Thanks.

[dyc3]

We get Arc<SocketMessage> from the channel, but we need to turn it into a Message (from the tungstenite crate) in order to call send. This is impossible to do without cloning the inner value of the Arc, which is what we are trying to avoid, or using unsafe code, which we also want to avoid.