fix(server): queue burst requests without rejecting conversions

base/pref.example.ini

@@ -290,6 +290,9 @@ log_level=info
 print_debug_info=false
 max_pending_connections=10240
 max_concurrent_threads=16
+;Maximum HTTP worker threads during bursts. Requests above this limit remain
+;queued instead of being rejected.
+max_server_threads=128
 max_allowed_rulesets=128
 max_allowed_rules=0
 max_allowed_download_size=0
@@ -302,9 +305,6 @@ async_fetch_ruleset=true
 skip_failed_links=true
 enable_request_coalescing=true
 coalesce_retry_on_5xx=true
-;Maximum time duplicate /sub requests wait for an in-flight conversion before
-;returning 503, so HTTP workers are not exhausted by identical long requests.
-coalesce_wait_timeout_ms=2000
 ;0 disables completed response caching. Values above 5 seconds are clamped to 5.
 response_cache_ttl=0
 ;0 disables the limiter. A small value is safer on single-core deployments.

base/pref.example.toml

@@ -348,6 +348,9 @@ log_level = "info"
 print_debug_info = false
 max_pending_connections = 10240
 max_concurrent_threads = 16
+# Maximum HTTP worker threads during bursts. Requests above this limit remain
+# queued instead of being rejected.
+max_server_threads = 128
 max_allowed_rulesets = 64
 max_allowed_rules = 0
 max_allowed_download_size = 0
@@ -360,9 +363,6 @@ async_fetch_ruleset = true
 skip_failed_links = true
 enable_request_coalescing = true
 coalesce_retry_on_5xx = true
-# Maximum time duplicate /sub requests wait for an in-flight conversion before
-# returning 503, so HTTP workers are not exhausted by identical long requests.
-coalesce_wait_timeout_ms = 2000
 # 0 disables completed response caching. If enabled, values above 5 seconds are clamped to 5.
 response_cache_ttl = 0
 # 0 disables the limiter. A small value is safer on single-core deployments.

base/pref.example.yml

@@ -161,6 +161,7 @@ advanced:
   print_debug_info: false
   max_pending_connections: 10240
   max_concurrent_threads: 16
+  max_server_threads: 128
   max_allowed_rulesets: 64
   max_allowed_rules: 0
   max_allowed_download_size: 0
@@ -173,6 +174,5 @@ advanced:
   skip_failed_links: true
   enable_request_coalescing: true
   coalesce_retry_on_5xx: true
-  coalesce_wait_timeout_ms: 2000
   response_cache_ttl: 0
   max_async_fetches: 2