ParallelDownloads in pacman 6.0: Picking a Per-Mirror Concurrency Limit
pacman 6.0 introduced the ParallelDownloads option in /etc/pacman.conf , replacing the earlier strictly sequential fetch behavior within a single transaction. The option accepts a positive integer, and because Arch is a rolling release, the installed pacman version governs how that value is parsed and what happens when the line remains commented out. Upgrade
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