fix: reduce default parallelism to 1, use lazy pool on manual start#2676
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Christian-Sidak wants to merge 1 commit into
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fix: reduce default parallelism to 1, use lazy pool on manual start#2676Christian-Sidak wants to merge 1 commit into
Christian-Sidak wants to merge 1 commit into
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Default parallelism of 24 caused eager pool initialization on every agent start, spawning hundreds of idle processes and consuming ~14 GB RAM with Codex ACP backends. Matches the lazy-start behavior already used by launch-time restore (see restore.rs F1 comment). Fixes block#2631 Signed-off-by: Christian-Sidak <61099993+Christian-Sidak@users.noreply.github.com>
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Summary
DEFAULT_AGENT_PARALLELISMfrom 24 to 1 intypes.rslazy: true) instart_managed_agent_processto match launch-time restore behaviorProblem
With the default parallelism of 24, starting agents eagerly initializes the full worker pool via
spawn_agent_child(..., false, ...). With Codex ACP backends, each worker spawns multiple processes (adapter + app-server chain), resulting in ~220 idle processes and ~14 GB RSS for just four agents -- before any work arrives.The launch-time restore path already uses
lazy: truewith an explicit comment ("eager restore... silently reintroduces N idle brains on every launch"). The manual-start path lacked the same protection.Changes
types.rs:DEFAULT_AGENT_PARALLELISM24 → 1. Desktop installations should default to a single worker; higher parallelism remains available as an explicit setting.runtime.rs:start_managed_agent_processnow passeslazy: truetospawn_agent_child, deferring pool initialization until the first event arrives.types/tests.rs: two regression tests pinningDEFAULT_AGENT_PARALLELISM == 1and verifying legacy records without an explicit parallelism field deserialize to 1.Test plan
default_agent_parallelism_is_one-- assertsDEFAULT_AGENT_PARALLELISM == 1managed_agent_record_without_parallelism_defaults_to_one-- legacy JSON without aparallelismkey deserializes to 1BUZZ_ACP_LAZY_POOL=trueis already used byspawn_agent_childwhenlazy=true(runtime.rs line 1722), so the env-var path is covered by the existing harnessFixes #2631