X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/029f4e3fda0aaddabf8312586a1a6d73643967fc..b1cb4abc8daa07074cb34cc8a9076763176c097e:/doc/doxygen/platform.doc diff --git a/doc/doxygen/platform.doc b/doc/doxygen/platform.doc index 1d4a719b3b..9dcf506be7 100644 --- a/doc/doxygen/platform.doc +++ b/doc/doxygen/platform.doc @@ -1,4 +1,4 @@ -/*! \page platform Step 1: %Model the underlying platform +/*! \page platform %Model the underlying platform @tableofcontents @@ -35,10 +35,10 @@ available and very well tested. The XML checking is done based on the Document Type Definition (DTD) file, available at -http://simgrid.gforge.inria.fr/simgrid.dtd. +http://simgrid.gforge.inria.fr/simgrid/simgrid.dtd. If you read the DTD, you should notice the following: -\li The platform tags contain a version attribute; the current version is 3. +\li The platform tags contain a version attribute; the current version is 4. This property might be used in the future to provide backwards compatibility. \li The DTD contains definitions for the two files used by SimGrid (i.e., @@ -145,14 +145,14 @@ routing | yes | Full\| Floyd\| Dijkstra\| DijkstraCache\| None\| V Example: -\verbatim +\code -\endverbatim +\endcode In this example, AS0 contains two hosts (host1 and host2). The route between the hosts goes through link1. @@ -206,8 +206,8 @@ and a separate text file whose syntax is exemplified below. #### Adding a trace file #### \verbatim - - + + \endverbatim @@ -241,8 +241,8 @@ It is also possible to specify whether the host is up or down by setting the #### Example: Expliciting the default value "ON" #### \verbatim - - + + \endverbatim @@ -259,8 +259,8 @@ of such a file is presented below. #### Adding a state file #### \verbatim - - + + \endverbatim @@ -339,6 +339,7 @@ sharing_policy | no | string | Sharing policy for the links between node bb_bw | no | int | Bandwidth for backbone (if any). See link section for syntax/details. If bb_bw and bb_lat (see below) attributes are omitted, no backbone is created (alternative cluster architecture described before). bb_lat | no | int | Latency for backbone (if any). See link section for syntax/details. If bb_lat and bb_bw (see above) attributes are omitted, no backbone is created (alternative cluster architecture described before). bb_sharing_policy | no | string | Sharing policy for the backbone (if any). See link section for syntax/details. +limiter_link | no | int | Bandwidth for limiter link (if any). This adds a specific link for each node, to set the maximum bandwidth reached when communicating in both directions at the same time. In theory this value should be 2*bw for fullduplex links, but in reality this might be less. This value will depend heavily on the communication model, and on the cluster's hardware, so no default value can be set, this has to be measured. More details can be obtained in "Toward Better Simulation of MPI Applications on Ethernet/TCP Networks" availability_file | no | string | Allows you to use a file as input for availability. Similar to hosts attribute. state_file | no | string | Allows you to use a file as input for states. Similar to hosts attribute. loopback_bw | no | int | Bandwidth for loopback (if any). See link section for syntax/details. If loopback_bw and loopback_lat (see below) attributes are omitted, no loopback link is created and all intra-node communication will use the main network link of the node. Loopback link is a \ref pf_sharing_policy_fatpipe "\b FATPIPE". @@ -1560,7 +1561,7 @@ Tag name | Description | Documentation \verbatim - + @@ -1607,7 +1608,7 @@ each of them will then be usable. \verbatim - + @@ -1709,8 +1710,7 @@ non-intuitive schema ... Something like that : + gw_dst="c_4_2-cl_4_2_router"> @@ -1718,16 +1718,14 @@ non-intuitive schema ... Something like that : + gw_dst="router_4"> + gw_dst="router_4"> @@ -1753,16 +1751,16 @@ complicated in using it, here is an example of it: \verbatim - + - - + + ... - + \endverbatim @@ -1776,7 +1774,7 @@ That is for example what is commonly done when using peers (see Section \ref pf_ \verbatim - + @@ -1822,7 +1820,7 @@ characteristics (lookup : time to resolve a route): \li Cluster: Cluster routing, specific to cluster tag, should not be used. -\subsection pf_switch Hey, I want to describe a switch but there is no switch tag ! +\subsection pf_switch I want to describe a switch but there is no switch tag ! Actually we did not include switch tag, ok. But when you're trying to simulate a switch, the only major impact it has when you're using @@ -1863,7 +1861,7 @@ id="3"/></route>), without trying to build new routes by aggregating the provided ones. You are also free to declare platform where the routing is not -symmetric. For example, add the following to the previous file: +symmetrical. For example, add the following to the previous file: \verbatim @@ -1878,89 +1876,4 @@ we've seen ways more weird situation in real settings (in fact, that's the realism of very regular platforms which is questionable, but that's another story). -\section pf_flexml_bypassing Bypassing the XML parser with your own C functions -NOTE THAT THIS DOCUMENTATION, WHILE STILL WORKING, IS STRONGLY DEPRECATED - -So you want to bypass the XML files parser, uh? Maybe doing some parameter -sweep experiments on your simulations or so? This is possible, and -it's not even really difficult (well. Such a brutal idea could be -harder to implement). Here is how it goes. - -For this, you have to first remember that the XML parsing in SimGrid is done -using a tool called FleXML. Given a DTD, this gives a flex-based parser. If -you want to bypass the parser, you need to provide some code mimicking what -it does and replacing it in its interactions with the SURF code. So, let's -have a look at these interactions. - -FleXML parser are close to classical SAX parsers. It means that a -well-formed SimGrid platform XML file might result in the following -"events": - - - start "platform_description" with attribute version="2" - - start "host" with attributes id="host1" power="1.0" - - end "host" - - start "host" with attributes id="host2" power="2.0" - - end "host" - - start "link" with ... - - end "link" - - start "route" with ... - - start "link_ctn" with ... - - end "link_ctn" - - end "route" - - end "platform_description" - -The communication from the parser to the SURF code uses two means: -Attributes get copied into some global variables, and a surf-provided -function gets called by the parser for each event. For example, the event - - start "host" with attributes id="host1" power="1.0" - -let the parser do something roughly equivalent to: -\verbatim - strcpy(A_host_id,"host1"); - A_host_power = 1.0; - STag_host(); -\endverbatim - -In SURF, we attach callbacks to the different events by initializing the -pointer functions to some the right surf functions. Since there can be -more than one callback attached to the same event (if more than one -model is in use, for example), they are stored in a dynar. Example in -host_ptask_L07.c: -\verbatim - /* Adding callback functions */ - surf_parse_reset_parser(); - surfxml_add_callback(STag_surfxml_host_cb_list, &parse_cpu_init); - surfxml_add_callback(STag_surfxml_prop_cb_list, &parse_properties); - surfxml_add_callback(STag_surfxml_link_cb_list, &parse_link_init); - surfxml_add_callback(STag_surfxml_route_cb_list, &parse_route_set_endpoints); - surfxml_add_callback(ETag_surfxml_link_c_ctn_cb_list, &parse_route_elem); - surfxml_add_callback(ETag_surfxml_route_cb_list, &parse_route_set_route); - - /* Parse the file */ - surf_parse_open(file); - xbt_assert(!surf_parse(), "Parse error in %s", file); - surf_parse_close(); -\endverbatim - -So, to bypass the FleXML parser, you need to write your own version of the -surf_parse function, which should do the following: - - Fill the A__ variables with the wanted values - - Call the corresponding STag__fun function to simulate tag start - - Call the corresponding ETag__fun function to simulate tag end - - (do the same for the next set of values, and loop) - -Then, tell SimGrid that you want to use your own "parser" instead of the stock one: -\verbatim - surf_parse = surf_parse_bypass_environment; - MSG_create_environment(NULL); - surf_parse = surf_parse_bypass_application; - MSG_launch_application(NULL); -\endverbatim - -A set of macros are provided at the end of -include/surf/surfxml_parse.h to ease the writing of the bypass -functions. An example of this trick is distributed in the file -examples/msg/masterslave/masterslave_bypass.c - - */