Guard agains erlang:system_info(logical_processors) not always returning number

src/extauth.erl

@@ -99,10 +99,7 @@ worker_name(Pool, N) ->
 -spec pool_size(binary()) -> pos_integer().
 pool_size(Host) ->
     case ejabberd_option:extauth_pool_size(Host) of
-	undefined ->
-	    try erlang:system_info(logical_processors)
-	    catch _:_ -> 1
-	    end;
+	undefined -> misc:logical_processors();
 	Size ->
 	    Size
     end.

src/misc.erl

@@ -42,7 +42,8 @@
 	 is_mucsub_message/1, best_match/2, pmap/2, peach/2, format_exception/4,
 	 get_my_ipv4_address/0, get_my_ipv6_address/0, parse_ip_mask/1,
 	 crypto_hmac/3, crypto_hmac/4, uri_parse/1,
-	 match_ip_mask/3, format_hosts_list/1, format_cycle/1, delete_dir/1]).
+	 match_ip_mask/3, format_hosts_list/1, format_cycle/1, delete_dir/1,
+	 logical_processors/0]).
 
 %% Deprecated functions
 -export([decode_base64/1, encode_base64/1]).
@@ -451,9 +452,16 @@ best_match(Pattern, Opts) ->
 		end, #{}, Opts),
     element(2, lists:min(Ds)).
 
+-spec logical_processors() -> non_neg_integer().
+logical_processors() ->
+    case erlang:system_info(logical_processors) of
+	unknown -> 1;
+	V -> V
+    end.
+
 -spec pmap(fun((T1) -> T2), [T1]) -> [T2].
 pmap(Fun, [_,_|_] = List) ->
-    case erlang:system_info(logical_processors) of
+    case logical_processors() of
 	1 -> lists:map(Fun, List);
 	_ ->
 	    Self = self(),
@@ -477,7 +485,7 @@ pmap(Fun, List) ->
 
 -spec peach(fun((T) -> any()), [T]) -> ok.
 peach(Fun, [_,_|_] = List) ->
-    case erlang:system_info(logical_processors) of
+    case logical_processors() of
 	1 -> lists:foreach(Fun, List);
 	_ ->
 	    Self = self(),

src/mod_muc.erl

@@ -166,7 +166,7 @@ reload(ServerHost, NewOpts, OldOpts) ->
       fun(I) ->
 	      ?GEN_SERVER:cast(procname(ServerHost, I),
 			       {reload, AddHosts, DelHosts, NewHosts})
-      end, lists:seq(1, erlang:system_info(logical_processors))),
+      end, lists:seq(1, misc:logical_processors())),
     load_permanent_rooms(AddHosts, ServerHost, NewOpts),
     shutdown_rooms(ServerHost, DelHosts, OldRMod),
     lists:foreach(
@@ -193,7 +193,7 @@ procname(Host, I) when is_integer(I) ->
       <<(atom_to_binary(?MODULE, latin1))/binary, "_", Host/binary,
 	"_", (integer_to_binary(I))/binary>>, utf8);
 procname(Host, RoomHost) ->
-    Cores = erlang:system_info(logical_processors),
+    Cores = misc:logical_processors(),
     I = erlang:phash2(RoomHost, Cores) + 1,
     procname(Host, I).
 

src/mod_muc_sup.erl

@@ -51,7 +51,7 @@ procname(Host) ->
 %%% Supervisor callbacks
 %%%===================================================================
 init([Host]) ->
-    Cores = erlang:system_info(logical_processors),
+    Cores = misc:logical_processors(),
     Specs = lists:foldl(
 	      fun(I, Acc) ->
 		      [#{id => mod_muc:procname(Host, I),