Carthage/Carthage

High CPU usage attributed to `carthage` when blocking on tasks

Open

#126 opened on Nov 21, 2014

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bughelp wantedupdate

Description

During a long series of Git operations, carthage was spiking to > 200% CPU usage, despite the fact that most of the work was happening in git processes.

We may be unintentionally busy-waiting somewhere (perhaps because a task isn't quiet that should be?) or shelling out too frequently.

Contributor guide

Tech stack
swiftshell
Domain
toolingperformance
Issue type
performance
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
SwiftGitTask management
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
35
Research direction
Investigate the task scheduling in Carthage's source code, particularly in the Git operations module. Look for any busy wait loops or excessive polling when spawning git processes. Consider using instruments to profile CPU usage. The issue #126 mentions that CPU spikes occur during long Git operations, so focus on the code that handles asynchronous task blocking.