erlang-supervisor

来源： https://stackoverflow.com/questions/43372045/logging-errors-when-an-elixir-otp-supervisor-detects-a-crashed-process

来源： https://stackoverflow.com/questions/43372045/logging-errors-when-an-elixir-otp-supervisor-detects-a-crashed-process

问题 I have a test module and a simple_one_for_one supervisor. test.erl -module(test). -export([ run/1, do_job/1 ]). run(Fun) -> test_sup:start_child([Fun]). do_job(Fun) -> Pid = spawn(Fun), io:format("started ~p~n", [Pid]), {ok, Pid}. test_sup.erl -module(test_sup). -behaviour(supervisor). -export([start_link/0]). -export([init/1]). -export([start_child/1]). start_link() -> supervisor:start_link({local, ?MODULE}, ?MODULE, []). init(_Args) -> SupFlags = #{strategy => simple_one_for_one, intensity

问题 I'm very new to OTP, I'm trying to create simple example to understand supervisor behaviour: Here is simple increment server -module( inc_serv ). -behaviour( gen_server ). -export( [ start/0, inc/1, stop/0 ] ). -export( [ init/1, handle_call/3, terminate/2 ] ). start() -> gen_server:start_link( { local, ?MODULE }, ?MODULE, no_args, [] ). stop() -> gen_server:call( ?MODULE, stop ). inc( Num ) -> gen_server:call( ?MODULE, { num, Num } ). init( no_args ) -> io:format( "~p~n", [ "Increment server

问题 I'm very new to OTP, I'm trying to create simple example to understand supervisor behaviour: Here is simple increment server -module( inc_serv ). -behaviour( gen_server ). -export( [ start/0, inc/1, stop/0 ] ). -export( [ init/1, handle_call/3, terminate/2 ] ). start() -> gen_server:start_link( { local, ?MODULE }, ?MODULE, no_args, [] ). stop() -> gen_server:call( ?MODULE, stop ). inc( Num ) -> gen_server:call( ?MODULE, { num, Num } ). init( no_args ) -> io:format( "~p~n", [ "Increment server

问题 I'm using erlang as a bridge between services and I was wondering what advice people had for handling downed connections? I'm taking input from local files and piping them out to AMQP and it's conceivable that the AMQP broker could go down. For that case I would want to keep retrying to connect to the AMQP server but I don't want to peg the CPU with those connections attempts. My inclination is to put a sleep into the reboot of the AMQP code. Wouldn't that 'hack' essentially circumvent the

问题 I'm trying to understand what's happening here: I have a supervisor that is cyclically restarting one client without triggering the MaxR, MaxT mechanism. The client just crashes slowly enough never to trigger the rate limitation. There would have been another mechanism that uses supervisor:which_children/1 and delete_child/2, start_child/2 to adapt the set of children to reality (its scanning for USB devices trying to have one supervisor child per device found). This would normally behave

问题 I have a one_for_one supervisor that handles similar and totally independent children. When there is a problem with one child, repeatedly crashing and triggering: =SUPERVISOR REPORT==== 30-Mar-2011::13:10:42 === Supervisor: {local,gateway_sup} Context: shutdown Reason: reached_max_restart_intensity Offender: [{pid,<0.76.0>}, ... shutting itself down and also terminating all the innocent children that would just continue to run fine otherwise. How can I build a supervision tree out of standard

问题 I'm playing with code for supervisor trees taken from http://learnyousomeerlang.com/building-applications-with-otp but I get a noproc exception that I can't figure out when I try to get a supervisor to start the child process. This is my shell interaction: 1> application:start(test). root supervisor init ok 2> test_sup:start_service(service_sup,{service_worker, start_link,[]}). {ok,<0.39.0>} worker supervisor initialise (M: service_worker,F: start_link,A: []) 3> test_app:run(service_worker,[]

问题 Somebody told me that simple_one_for_one is very useful for chat applications, because each chat client is a server process (gen_server). Is this right? And I wonder why do we need it? Why not create only one center server (gen_server) to handle all chat client communication? Because maybe the number of chat clients is very large so only one server couldn't handle fast, make the system slow down? I think maybe creating too many servers like simple_one_for_one may take too much system resource