Add the count_process_dynamic service configuration option for dynami…

…cally adjusting the number of processes used for a single service instance (i.e., single service_id) based on changes in the rate of incoming service requests. Add the rate-based hibernate service configuration option for internal services (a list of options for conditional hibernation). #57 #56

src/ChangeLog

@@ -1,6 +1,15 @@
 # -*- coding: utf-8; tab-width: 4; -*-
 # ex: set fileencoding=utf-8 softtabstop=4 tabstop=4 expandtab:
 
+2013-12-13 Michael Truog   <mjtruog [at] gmail (dot) com>
+
+    * Add the count_process_dynamic service configuration option for
+      dynamically adjusting the number of processes used for a single
+      service instance (i.e., single service_id) based on changes in the
+      rate of incoming service requests
+    * Add the rate-based hibernate service configuration option for internal
+      services (a list of options for conditional hibernation)
+
 2013-12-11 Michael Truog   <mjtruog [at] gmail (dot) com>
 
     * Add cloudi_service_http_cowboy:close/1 for forcing a cowboy

src/cloudi.conf.in

@@ -291,7 +291,13 @@
         "tests/http_req/http_req_c.py",
         [],
         none, tcp, default,
-        5000, 5000, 5000, [api], undefined, 1, 1, 5, 300, []},
+        5000, 5000, 5000, [api], undefined,
+        1.0, 1, 5, 300,
+        [{count_process_dynamic,
+          [{rate_request_max, 1.1},
+           {rate_request_min, 0.9},
+           {count_max, 4.0},
+           {count_min, 0.25}]}]},
     {external,
         "/tests/http_req/",
         "@JAVA@",
@@ -304,14 +310,28 @@
         [],
         none,
         4294967195, 4294967195, 4294967195, % test limits
-        [api], undefined, 1, 5, 300, []},
+        [api], undefined, 1.0, 5, 300,
+        [{hibernate,
+          [{rate_request_min, 0.9}]},
+         {count_process_dynamic,
+          [{rate_request_max, 1.1},
+           {rate_request_min, 0.9},
+           {count_max, 2.0},
+           {count_min, 0.25}]}]},
     {internal,
         "/tests/http_req/",
         cloudi_service_http_req,
         [],
         none,
         101, 101, 101, % test limits
-        [api], undefined, 1, 5, 300, []},
+        [api], undefined, 1.0, 5, 300,
+        [{hibernate,
+          [{rate_request_min, 0.9}]},
+         {count_process_dynamic,
+          [{rate_request_max, 1.1},
+           {rate_request_min, 0.9},
+           {count_max, 2.0},
+           {count_min, 0.25}]}]},
     {internal,
         "/tests/http_req/",
         cloudi_service_filesystem,

src/lib/cloudi_core/src/cloudi_configuration.hrl

@@ -112,6 +112,20 @@
         % instead of a returned null response message
         response_timeout_immediate_max = 20000 % milliseconds
             :: cloudi_service_api:response_timeout_immediate_max_milliseconds(),
+        % should the process count be varied automatically based on the
+        % rate of service processing within a specific time period.
+        % the count max/min specify limits for the count_process changes
+        % as either floating point percentages (the result is rounded) or
+        % as integer absolutes.
+        count_process_dynamic = false
+            :: false |
+               list({period,
+                     cloudi_rate_based_configuration:period_seconds()} |
+                    {rate_request_max, number()} | % service reqs/second
+                    {rate_request_min, number()} | % service reqs/second
+                    {count_max, number()} | % float multiplier or
+                    {count_min, number()}) | % integer absolute
+               tuple(),
         % provide a scope for all subscribe/unsubscribe and messaging
         % (i.e., all service name usage is within the scope).  Using a
         % different scope can help avoid contention when using an immediate
@@ -124,12 +138,17 @@
         % checked during service startup (e.g., after service restarts).
         % (all time parameters are specified in milliseconds)
         monkey_latency = false
-            :: list({time_uniform_min, pos_integer()} |
-                    {time_uniform_max, pos_integer()} |
-                    {time_gaussian_mean, pos_integer()} |
+            :: list({time_uniform_min,
+                     cloudi_runtime_testing:time_milliseconds()} |
+                    {time_uniform_max,
+                     cloudi_runtime_testing:time_milliseconds()} |
+                    {time_gaussian_mean,
+                     cloudi_runtime_testing:time_milliseconds()} |
                     {time_gaussian_stddev, float()} |
-                    {time_absolute, pos_integer()}) |
-               system | false,
+                    {time_absolute,
+                     cloudi_runtime_testing:time_milliseconds()}) |
+               system | false |
+               tuple(),
         % cause service termination based on the probability parameter
         % (checked for each service request and info message, if necessary).
         % If "system" is set, the cloudi_core Erlang application env value
@@ -139,7 +158,8 @@
         monkey_chaos = false
             :: list({probability_request, float()} |
                     {probability_day, float()}) |
-               system | false,
+               system | false |
+               tuple(),
 
         % Only Relevant For Internal Services:
 
@@ -182,9 +202,14 @@
             :: boolean(),
         % should a mostly idle service hibernate automatically to conserve
         % memory at the expense of extra garbage collections and an empty
-        % stack trace.
+        % stack trace.  if a list is provided, hibernate will occur when
+        % the rate of service processing drops below the minimum specified.
         hibernate = false
-            :: boolean(),
+            :: boolean() |
+               list({period,
+                     cloudi_rate_based_configuration:period_seconds()} |
+                    {rate_request_min, number()}) | % service reqs/second
+               tuple(),
         % should the service be reloaded automatically when an Erlang module
         % file changes?  should only be used during service development.
         reload = false
@@ -194,8 +219,6 @@
         automatic_loading = true
             :: boolean()
     }).
--define(CONFIG_SERVICE_OPTIONS_EXTERNAL_SIZE,
-        (#config_service_options.application_name - 1)).
 
 % internal service parameters
 -record(config_service_internal,

src/lib/cloudi_core/src/cloudi_configurator.erl

@@ -175,9 +175,12 @@ service_start(#config_service_internal{
             Error
     end;
 
-service_start(#config_service_external{count_process = Count} = Service,
+service_start(#config_service_external{count_process = Count,
+                                       count_thread = CountThread} = Service,
               Timeout) ->
-    service_start_external(concurrency(Count), Service, timeout_decr(Timeout)).
+    NewCountThread = concurrency(CountThread),
+    service_start_external(concurrency(Count), Service,
+                           NewCountThread, timeout_decr(Timeout)).
 
 service_stop(#config_service_internal{} = Service, Remove, Timeout)
     when is_boolean(Remove) ->
@@ -199,7 +202,7 @@ concurrency(I)
     when is_float(I) ->
     if
         I > 1.0 ->
-            ceil(I * erlang:system_info(schedulers));
+            cloudi_math:ceil(I * erlang:system_info(schedulers));
         I > 0.0, I < 1.0 ->
             erlang:max(1, erlang:round(I * erlang:system_info(schedulers)));
         I == 1.0 ->
@@ -584,23 +587,21 @@ service_start_internal(Count0,
                            uuid = ID} = Service, Timeout) ->
     Count1 = Count0 - 1,
     case cloudi_services_monitor:monitor(cloudi_spawn, start_internal,
-                                         [Count1,
-                                          Module, Args, TimeoutInit,
+                                         [Module, Args, TimeoutInit,
                                           Prefix, TimeoutAsync, TimeoutSync,
                                           DestRefresh, DestListDeny,
                                           DestListAllow, Options, ID],
-                                         MaxR, MaxT, ID, Timeout) of
+                                         Count1, 1, MaxR, MaxT, ID, Timeout) of
         ok ->
             service_start_internal(Count1, Service, Timeout);
         {error, _} = Error ->
             Error
     end.
 
-service_start_external(0, Service, _) ->
+service_start_external(0, Service, _, _) ->
     {ok, Service};
 service_start_external(Count0,
                        #config_service_external{
-                           count_thread = CountThread,
                            file_path = FilePath,
                            args = Args,
                            env = Env,
@@ -616,17 +617,19 @@ service_start_external(Count0,
                            options = Options,
                            max_r = MaxR,
                            max_t = MaxT,
-                           uuid = ID} = Service, Timeout) ->
+                           uuid = ID} = Service, CountThread, Timeout) ->
+    Count1 = Count0 - 1,
     case cloudi_services_monitor:monitor(cloudi_spawn, start_external,
-                                         [concurrency(CountThread),
+                                         [CountThread,
                                           FilePath, Args, Env,
                                           Protocol, BufferSize, TimeoutInit,
                                           Prefix, TimeoutAsync, TimeoutSync,
                                           DestRefresh, DestListDeny,
                                           DestListAllow, Options, ID],
+                                         Count1, CountThread,
                                          MaxR, MaxT, ID, Timeout) of
         ok ->
-            service_start_external(Count0 - 1, Service, Timeout);
+            service_start_external(Count1, Service, CountThread, Timeout);
         {error, _} = Error ->
             Error
     end.
@@ -700,21 +703,3 @@ timeout_decr(infinity) ->
 timeout_decr(Timeout) when is_integer(Timeout) ->
     Timeout - ?TIMEOUT_DELTA.
 
-ceil(X) ->
-    T = erlang:trunc(X),
-    if
-        X > T ->
-            T + 1;
-        true ->
-            T
-    end.
-
-%floor(X) ->
-%    T = erlang:trunc(X),
-%    if
-%        X < T ->
-%            T - 1;
-%        true ->
-%            T
-%    end.
-

src/lib/cloudi_core/src/cloudi_core.app.src.in

@@ -14,11 +14,13 @@
         cloudi_lists,
         cloudi_logger,
         cloudi_logger_interface,
+        cloudi_math,
         cloudi_nodes,
         cloudi_os_spawn,
         cloudi_pool,
         cloudi_pool_sup,
         cloudi_proplists,
+        cloudi_rate_based_configuration,
         cloudi_request,
         cloudi_response,
         cloudi_runtime_testing,

src/lib/cloudi_core/src/cloudi_math.erl

@@ -0,0 +1,93 @@
+%-*-Mode:erlang;coding:utf-8;tab-width:4;c-basic-offset:4;indent-tabs-mode:()-*-
+% ex: set ft=erlang fenc=utf-8 sts=4 ts=4 sw=4 et:
+%%%
+%%%------------------------------------------------------------------------
+%%% @doc
+%%% ==Math operations==
+%%% @end
+%%%
+%%% BSD LICENSE
+%%% 
+%%% Copyright (c) 2009-2013, Michael Truog <mjtruog at gmail dot com>
+%%% All rights reserved.
+%%% 
+%%% Redistribution and use in source and binary forms, with or without
+%%% modification, are permitted provided that the following conditions are met:
+%%% 
+%%%     * Redistributions of source code must retain the above copyright
+%%%       notice, this list of conditions and the following disclaimer.
+%%%     * Redistributions in binary form must reproduce the above copyright
+%%%       notice, this list of conditions and the following disclaimer in
+%%%       the documentation and/or other materials provided with the
+%%%       distribution.
+%%%     * All advertising materials mentioning features or use of this
+%%%       software must display the following acknowledgment:
+%%%         This product includes software developed by Michael Truog
+%%%     * The name of the author may not be used to endorse or promote
+%%%       products derived from this software without specific prior
+%%%       written permission
+%%% 
+%%% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+%%% CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+%%% INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+%%% OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+%%% DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+%%% CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+%%% SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+%%% BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+%%% SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+%%% INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+%%% WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+%%% NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+%%% OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+%%% DAMAGE.
+%%%
+%%% @author Michael Truog <mjtruog [at] gmail (dot) com>
+%%% @copyright 2009-2013 Michael Truog
+%%% @version 1.3.1 {@date} {@time}
+%%%------------------------------------------------------------------------
+
+-module(cloudi_math).
+-author('mjtruog [at] gmail (dot) com').
+
+%% external interface
+-export([ceil/1, floor/1]).
+
+%%%------------------------------------------------------------------------
+%%% External interface functions
+%%%------------------------------------------------------------------------
+
+%%-------------------------------------------------------------------------
+%% @doc
+%% ===Provide a ceiling function.===
+%% @end
+%%-------------------------------------------------------------------------
+
+-spec ceil(number()) -> integer().
+
+ceil(X) ->
+    T = erlang:trunc(X),
+    if
+        X > T ->
+            T + 1;
+        true ->
+            T
+    end.
+
+%%-------------------------------------------------------------------------
+%% @doc
+%% ===Provide a floor function.===
+%% @end
+%%-------------------------------------------------------------------------
+
+-spec floor(number()) -> integer().
+
+floor(X) ->
+    T = erlang:trunc(X),
+    if
+        X < T ->
+            T - 1;
+        true ->
+            T
+    end.
+