rename an option and improve its doc: maxmin/concurrency-limit

diff --git a/doc/doxygen/options.doc b/doc/doxygen/options.doc
index 5fc516d..4799993 100644 (file)
--- a/doc/doxygen/options.doc
+++ b/doc/doxygen/options.doc
@@ -202,9 +202,17 @@ price of a reduced numerical precision.
 \subsection options_concurrency_limit Concurrency limit
 
 The maximum number of variables per resource can be tuned through
-the \b maxmin/concurrency_limit item (default value: -1, meaning no such limitation). 
-Setting a higher value can lift some limitations, such as the number of 
-concurrent processes running on a single host.
+the \b maxmin/concurrency-limit item. The default value is -1, meaning that
+there is no such limitation. You can have as many simultaneous actions per
+resources as you want. If your simulation presents a very high level of
+concurrency, it may help to use e.g. 100 as a value here. It means that at
+most 100 actions can consume a resource at a given time. The extraneous actions
+are queued and wait until the amount of concurrency of the considered resource
+lowers under the given boundary.
+
+Such limitations help both to the simulation speed and simulation accuracy
+on highly constrained scenarios, but the simulation speed suffers of this
+setting on regular (less constrained) scenarios so it is off by default.
 
 \subsection options_model_network Configuring the Network model
 
@@ -1143,6 +1151,7 @@ It can be done by using XBT. Go to \ref XBT_log for more details.
 - \c host/model: \ref options_model_select
 
 - \c maxmin/precision: \ref options_model_precision
+- \c maxmin/concurrency-limit: \ref options_concurrency_limit
 
 - \c msg/debug-multiple-use: \ref options_msg_debug_multiple_use
 

diff --git a/examples/smpi/replay_multiple/replay_multiple.tesh b/examples/smpi/replay_multiple/replay_multiple.tesh
index d987745..72f83bb 100644 (file)
--- a/examples/smpi/replay_multiple/replay_multiple.tesh
+++ b/examples/smpi/replay_multiple/replay_multiple.tesh
@@ -3,9 +3,10 @@ p Test the replay with multiple instances
 p first generate the deployment file
 $ ${srcdir:=.}/generate_multiple_deployment.sh -platform ${srcdir:=.}/../../platforms/small_platform_with_routers.xml -hostfile ${srcdir:=.}/../hostfile  ${srcdir:=.}/description_file ${srcdir:=.}/deployment.xml
 
+p This test needs maxmin/concurrency-limit=100 because it stats 64 hosts on 5 machines.
 ! timeout 120
-$ ./replay_multiple description_file ${srcdir:=.}/../../platforms/small_platform_with_routers.xml ${srcdir:=.}/deployment.xml --log=smpi.:info --cfg=maxmin/concurrency_limit:100
-> [0.000000] [xbt_cfg/INFO] Configuration change: Set 'maxmin/concurrency_limit' to '100'
+$ ./replay_multiple description_file ${srcdir:=.}/../../platforms/small_platform_with_routers.xml ${srcdir:=.}/deployment.xml --log=smpi.:info --cfg=maxmin/concurrency-limit:100
+> [0.000000] [xbt_cfg/INFO] Configuration change: Set 'maxmin/concurrency-limit' to '100'
 > [0.000000] [msg_test/INFO] Initializing instance 1 of size 32
 > [0.000000] [msg_test/INFO] Initializing instance 2 of size 32
 > [0.000000] [smpi_kernel/INFO] You did not set the power of the host running the simulation.  The timings will certainly not be accurate.  Use the option "--cfg=smpi/host-speed:<flops>" to set its value.Check http://simgrid.org/simgrid/latest/doc/options.html#options_smpi_bench for more information.

diff --git a/src/simgrid/sg_config.cpp b/src/simgrid/sg_config.cpp
index 8ac7ca7..e10539e 100644 (file)
--- a/src/simgrid/sg_config.cpp
+++ b/src/simgrid/sg_config.cpp
@@ -390,9 +390,10 @@ void sg_config_init(int *argc, char **argv)
     simgrid::config::bindFlag(sg_maxmin_precision, "maxmin/precision",
                               "Numerical precision used when computing resource sharing (in flops/sec or bytes/sec)");
 
-    simgrid::config::bindFlag(sg_concurrency_limit, "maxmin/concurrency_limit",
+    simgrid::config::bindFlag(sg_concurrency_limit, "maxmin/concurrency-limit",
                               "Maximum number of concurrent variables in the maxmim system. Also limits the number of "
                               "processes on each host, at higher level. (default: -1 means no such limitation)");
+    xbt_cfg_register_alias("maxmin/concurrency-limit", "maxmin/concurrency_limit");
 
     /* The parameters of network models */
 

diff --git a/src/surf/maxmin.cpp b/src/surf/maxmin.cpp
index 253ebd1..dc0280b 100644 (file)
--- a/src/surf/maxmin.cpp
+++ b/src/surf/maxmin.cpp
@@ -24,7 +24,7 @@ typedef struct s_dyn_light {
 
 double sg_maxmin_precision = 0.00001; /* Change this with --cfg=maxmin/precision:VALUE */
 double sg_surf_precision   = 0.00001; /* Change this with --cfg=surf/precision:VALUE */
-int sg_concurrency_limit   = -1;      /* Change this with --cfg=maxmin/concurrency_limit:VALUE */
+int sg_concurrency_limit   = -1;      /* Change this with --cfg=maxmin/concurrency-limit:VALUE */
 
 static void *lmm_variable_mallocator_new_f();
 static void lmm_variable_mallocator_free_f(void *var);