Rework the Transport layer to simplify it and improve its performance

[simgrid.git] / ChangeLog

SimGrid (3.0.1) unstable; urgency=low

  XBT:
  * Unfortunately, I had missed 5 misnamed functions:
      xbt_fifo_item_t xbt_fifo_newitem(void);
      void xbt_fifo_freeitem(xbt_fifo_item_t);
      xbt_fifo_item_t xbt_fifo_getFirstItem(xbt_fifo_t l);
      xbt_fifo_item_t xbt_fifo_getNextItem(xbt_fifo_item_t i);
      xbt_fifo_item_t xbt_fifo_getPrevItem(xbt_fifo_item_t i);
    They're now deprecated. Please use their new versions:
      xbt_fifo_item_t xbt_fifo_new_item(void);
      void xbt_fifo_free_item(xbt_fifo_item_t);
      xbt_fifo_item_t xbt_fifo_get_first_item(xbt_fifo_t l);
      xbt_fifo_item_t xbt_fifo_get_next_item(xbt_fifo_item_t i);
      xbt_fifo_item_t xbt_fifo_get_prev_item(xbt_fifo_item_t i);
    [AL]
  * Bugfix: really disconnect fifo items which are remove_item()ed [AL]
  * Documentation: xbt_log module unmercifully reworked [MQ]
  
  MSG:
  * Add addtionnal checkings on channel values in communicating functions.

  GRAS performance improvements:
  * Actually implement gras_datadesc_copy() so that we don't have to mimick
    RL communication on top of SG since it's so uneffective. 
    It may also be used for inter-thread communication in RL, one day. [MQ]
  * Use gras_datadesc_copy() to exchange messages on top of SG [MQ]
    Allows to:
    - improve message exchange performance on top of SG
    - deprecate transport_plugin_sg.c:gras_trp_sg_chunk_send() & recv()
  * Don't exchange on the network the size of the used part of buffer,
    instead, specify the possible buffer size to read(). [MQ] 
    Advantages:
     - reduces the amount of read/write calls (one pair per exchange)
     - reduces the amount of exchanged data (the size)
     - allows to retrieve all arrived data on receiver side, if we don't need
       it right now (subsequent read will peek the buffer)
     - allows the receiver to proceed with the begining of the stream before
       everything is arrived
     - make it possible to build an iov transport (using readv/writev)
    Extra difficulty: 
     - take care of the data with non-stable storage (like stacked data),
       and bufferize them.
  * If possible, TCP send uses vector I/O (when writev() is here) [MQ]
     - Don't use it for receive since we send data sizes and data on the
       same stream, so we wouldn't be able to chain large amount of chunks
       before having to flush the stuff to read the size.
  * Rework the transport plugin mecanism to simplify it and reduce the
    amount of pointer dereferencement when searching for the right function 
    to use. [MQ]

  * I guess that now, we do almost as few system calls as possible while
    doing as few data copy as possible.

    To improve it further, we could try to send all the sizes first and then
    all the data (to use iov on receiving size), but it's only a partial
    solution: when you have 2 dimensional data, the sizes of the second
    dimension is data of the first dimension, so you need 3 streams.

    I'm not sure the potential performance gains justify the coding burden.
    
 --

SimGrid (3.00) stable; urgency=low
  
 SURF:
  * New! Give the possibility to hijack the surf parser and thus bypass 
    MSG_create_environment and MSG_launch_application. Have a look at
    examples/msg/msg_test_surfxml_bypassed.c to see how it can be done.
        
 -- Arnaud Legrand <simgrid-devel@lists.gforge.inria.fr>  Sat, 20 Aug 2005 23:25:25 -0700

SimGrid (2.96) unstable; urgency=low

  AKA SimGrid 3 rc 2.
  
  XBT:
  * New! Exception handling with setjmp or such (code from OSSP ex) [MQ]
    This deprecates the xbt_error_t mecanisms. 
    It modifies (simplifies) all XBT and GRAS API.
    MSG API keeps unchanged (exceptions raised by XBT are catched from 
     within MSG and masked with existing error handling facilities)

  SURF:
  * New! Add a FATPIPE model. [AL]
  * New! Add a parallel task model. [AL]
  * New! Add automatically a loopback interface (in the default
    network model) if none was precised.

  MSG
  * Bugfix: MSG_process_resume now works with the current running process. 
    [AL]
  * New! Add MSG_parallel_task_create and MSG_parallel_task_execute. [AL]
  * Modification of MSG_task_get_compute_duration. Once a task has been
    processed, the value returned by this function is now equal to 0. [AL]
  * New! Add double MSG_task_get_remaining_computation(m_task_t task) and
    MSG_error_t MSG_task_cancel(m_task_t task). Add a state
    (MSG_TASK_CANCELLED) to MSG_error_t corresponding to the cancelation
    of a m_task. For now, MSG_task_cancel only works with computation
    tasks. [AL]
  * New! Add double MSG_get_host_speed(m_host_t h) that returns the speed
    of the processor (in Mflop/s) regardless of the current load on the
    machine. [AL]
  * API Change: use proper naming convention for MSG_getClock and 
    MSG_process_isSuspended: MSG_get_clock and MSG_process_is_suspended.
    [AL]
  * New! Add void MSG_task_set_priority(m_task_t task, double priority). 
    This function changes the priority of a computation task. This priority
    doesn't affect the transfer rate. A priority of 2 will make a task 
    receive two times more cpu power than the other ones. This function 
    has been added to suit the needs of Nguyen The Loc and hasn't been that
    much tested yet. So if it fails, please report it and send me your code. 
    [AL]
  * API Change: removed all functions and types that were marked "deprecated" 
    since many months. Renamed MSG_global_init_args to MSG_global_init.

 -- Da SimGrid team <simgrid-devel@lists.gforge.inria.fr>  Mon,  8 Aug 2005 17:58:47 -0700

SimGrid (2.95) unstable; urgency=low

  XBT
  * Steal some nice code to GNU pth to fix context detection and usage [AL]
  * Cleanup in the xbt_config API; add configuration callbacks. [MQ]
  * Cleanup in the initialization API: the unused "defaultlog" is dead. [MQ]

  SURF
  * Bugfix: Allow absolute paths for platform description files [MQ]
  * Bugfix: do free the variables after use. Leads to drastic performance 
    improvement [AL] 
  * Implement max_duration (ie, timeouts) on resources [AL]

  MSG
  * Implement MSG_config to configure MSG at runtime. xbt_cfg test on a real
    case ;) [MQ]
  * Implement MSG_channel_select_from() to help GRAS now that SURF provide
    the needed support (timeouts) [AL]

  GRAS (new features)
  * Implement measurement sockets. You can now get the bandwidth between two
    hosts thanks to AMOK (see below). [MQ]
  * gras_datadesc_dynar() builds a dynar type descriptor, allowing to send
    dynar over the network (yeah) [MQ]
  * Real (even if simplistic) implementation of gras_os_myname() on RL [MQ]
  * simple/static token-ring example. [Alexandre Colucci and MQ]
  * Use MSG_channel_select_from() and remove the *slow* hack we had to put
    in place before [MQ]
  
  GRAS (bug fixes)
  * Differentiate the types "char[22]" and "unsigned char[22]" in automatic
    type parsing. "short" and "long" modifiers were also ignored; other
    modifier (such as reference level) are still ignored. [MQ] 
  * Embeed the buffer size within the buffer itself on SG. [MQ]
    That way, send() are atomic and cannot get intermixed anymore (at least
    the ones which are less than 100k; bigger messages still have the issue)
  * Array size pushed by the field, not by the field type (or each
    and every long int will push stuff to the cbps) [MQ]
  * use select() to sleep since it allows to portably sleep less than one
    second. [MQ]

  GRAS (minor cleanups)
  * <project>.Makefile.local (generated from gras_stub_generator) |MQ]:
    - Do clean .o files
    - Compile with -g
  * Type Callbacks now receive the gras_datadesc_type_t they work on as argument.
  * type category 'ignored' killed as it was never used and were difficult
    to transmit.
  * whether a type can cycle or not is now a flag, leaving room for more
    flags (as "ignored", if we feel the need one day ;)
  * Rename raw sockets to measurement sockets since "raw" has another
    meaning in networking community. 
  
  AMOK 
  * Advanced Metacomputing Overlay Kit introduction. It is based over GRAS
    and offers features not belonging to GRAS but that most applications
    need. One day, it may be a set of plugins loadable at runtime.
  * New module: bandwidth 
    bandwidth measurement between arbitrary nodes running this module. [MQ]

 -- Da SimGrid team <simgrid-devel@lists.gforge.inria.fr>  Thu, 30 Jun 2005 16:29:20 -0700

SimGrid (2.94) unstable; urgency=low

  The first beta release of SimGrid 3 !

  >>>Arnaud<<<
  (documentation)
  * Update the main page and the FAQ. Adding references to gforge.

  (gras)
  * Add a gras_os_getpid function.

  (msg)
  * Add MSG_task_get_compute_duration() and MSG_task_get_data_size()
  * Extend the logs so that they also print PID, hostname, date, ... if
    available.
  * Convert the MSG example to the use of xbt_logs instead of PRINT_MESSAGE,
    and kill the old version which were in testsuite/
  * Rewrite tools/MSG_visualization/colorize.pl for using with logs instead
    of PRINT_MESSAGE

  (xbt)
  * Add xbt_os_time(). As the rest of xbt/portability, this is not public
    for users. Instead, each programming environment (GRAS, MSG,...) use it
    when needed to provide such a feature to users.
    Don't shortcut the mecanism or you will also shortcut the virtualization
    you need on the simulator.

  >>>Martin<<<
  (infrastructure)
  * Cleanups in configury with regard to compile optimization/warning flags.
    Also add -fno-loop-optimize to any powerpc since it's the optimization
    killing gcc (< 3.4.0).
  * Doxygen cleanups: move MSG examples, kill the second Doxygen phase
    needed by MSG examples complications
  * Borrow configury beautifications from PHP

  (xbt)
  * Bugfix: XBT_LOG_NEW_DEFAULT_CATEGORY now compiles without compiler
    warning (thanks loris for stumbling into this one).
  * Bugfix: stop loading private headers (gras_config.h) from the public
    ones (xbt/swag.h).

  (gras)
  * Change SIMGRID_INSTALL_PATH to GRAS_ROOT in Makefiles generated for user.
  * Rename gras_get_my_fqdn to gras_os_myname and implement it in the simulator
    RL would imply a DNS resolver, which is *hard* to do in a portable way
    (and therefore delayed).
  * Implement a real timer mecanism and use it in timing macros. This allows
    to avoid rounding errors and get a 0.000005 sec precision in timing
    macros. While I was at it, various cleanups:
     - allow to declare more than one timed section per file (fix a stupid bug)
     - move some private declaration to the right place
     - merge conditional execution and timing macros into emulation module
     - document the module
     - make sure the module cleanups its mess on gras_exit
  * Documentation improvements:
     - (new) how to compile applications using GRAS
     - (new) emulation support (timing macros)

 -- Da SimGrid team <simgrid-devel@lists.gforge.inria.fr>  Fri, 13 May 2005 10:49:31 +0200

SimGrid (2.93) unstable; urgency=low

  Alpha 4 on the path to SimGrid 3 (aka the "neuf-trois" version)

  [Arnaud]
   - Use Paje properly where used. Still to be sanitized properly.
   - Portability fix: Add an implementation of the contexts using pthread

  [Martin]
  (misc)
   - Add xbt_procname(): returns the name of the current process.
     Use it to show the current process's name in all logging.
  (infrastructure)
   - fix detection of older flex version and the reaction, since we do
     depend on modern ones (we use lex_destroy)
   - Better separation of SG and RL in the libs: remove all simulation code
     from libgras. As a result, this lib is now only 200k when stripped.
     Some of the xbt modules may also be duplicated (two sets and such) and
     should be cleaned/killed before SG3.
   - Insist on using xlC on AIX because of weird problems involving gcc there.
   - Cleanup the make remote stuff. This is now done by scripts
     tools/graspe-{master,slave} (GRAS Platform Expender). This is still
     mainly for our private use, but we're working on changing them to user
     tools, too.
  (gras)
   - Bugfix: flush the socket on close only if there is some *output*.
   - Bugfix: flush idempotent when there's nothing to send (don't send size=0)
  (msg)
   - Add MSG_task_get_name. The task names are mainly for debugging purpose,
     but anyway.

 -- SimGrid team <simgrid2-users@listes.ens-lyon.fr>  Fri,  4 Mar 2005 14:32:37 -0800

SimGrid (2.92) unstable; urgency=low

  Alpha 3 on the path to SimGrid 3
  
  [Arnaud]
  (gras)
   - New! First try of benchmarking macros.
   - New! First try so that gras_stub_generator generate deployment and
     remote compilation helpers.
  (msg)
   - Bugfix: Initialization fix in msg_test.

  [Martin]
  (surf)
   - Bugfix: applied patch to lexer so that it doesn't need a huge heap.
  (xbt)
   - Bugfix: let dicts work with NULL content (_foreach didn't) and cleanups
  (gras)
   - API Change: gras_os_sleep to take the amount of seconds as a double.
     Accepting an int was error prone since it was the only location where
     seconds were coded as such. It leaded to damn rounding errors.
   - Bugfix: Hard to belive that timers ever worked before this.

 -- SimGrid team <simgrid2-users@listes.ens-lyon.fr>  Wed, 23 Feb 2005 22:09:21 +0100

SimGrid (2.91) unstable; urgency=low

  Alpha 2 on the path to SimGrid 3
  
  [Arnaud]
  (surf)
   - Bug fix in the lmm_solver.
  (msg)
   - New! Interface to Paje (see http://www-id.imag.fr/Logiciels/paje/) 
     through the function MSG_paje_output.
   - New! Introducing two new functions MSG_process_kill() and MSG_process_killall().
   - It is possible to bound the rate of a communication in MSG with 
     MSG_task_put_bounded() (was already in the previous version but I had forgotten 
     to write it in the changelog).
   - Bug fix to let GRAS run on top of MSG until we move it directly on top
     of the SURF.
    
  [Martin]
  (infrastructure)
   - Various cleanups to the autotools stuff
   - Begin to move Gras examples to examples/gras/
   - Let make distcheck work again (yeah!)
  (documentation)
   - documentation overhauled using doxygen. 
     gtk-doc-tools is dead in SimGrid now.
   - Automatically extract all existing logging categories, and add the list
     to the documentation (long standing one, to say the less)
  (gras)
   - Cleanup the known architecture table. Reorder the entries to group what
     should be, and use a more consistent naming scheme.
     (some of the test dataset are still to be regenerated)
   - New! Allow library to register globals on each process just as userdata
     does. 
      This is implemented using a xbt_dict and not a xbt_set, so we loose the
       lookup time (for now).
      Use it in msg and trp.
      This cleans a lot the internals and helps enforcing privacy of the
       headers between the gras components.
   - New! Add a timer mechanism, not unlike cron(8) and at(1). 
   - Bugfix: gras_os_time was delirious in RL.
   - Bugfix: gras_trp_select/RL don't run into the wall when asked to select
     onto 0 sockets.
   - Reenable GRAS now that it works.

 -- Arnaud Legrand <Arnaud.Legrand@imag.fr>  Mon, 14 Feb 2005 14:02:13 -0800

SimGrid (2.90) unstable; urgency=low

  Alpha 1 on the path to SimGrid 3

  * It is a long time since the last release of SimGrid. I'm sorry about
    that but as I had told you, I was rewriting a lot of things. I apologize 
    to those who had been reporting bugs to me and that I had not answered. 
    If your bug is still in the new version, please tell me. Here is a 
    summary of the main changes.

  * REVOLUTION 1: The SimGrid project has merged with the GRAS project
    lead by Martin Quinson. As a consequence SimGrid gains a lot in
    portability, speed, and a lot more but you'll figure it out later. 
    SimGrid now comprises 3 different projects : MSG, GRAS and SMPI. 
    I wanted to release the new MSG as soon as possible and I have 
    broken GRAS, which is the reason why, for now, only MSG is fully 
    functional. A laconic description of these projects is available 
    in the documentation.
  
  * REVOLUTION 2: I have removed SG and I am now using a new simulation
    kernel optimized for our needs (called SURF but only the developers
    should use it). Hence, MSG is now roughly 30 times faster and I think
    that by rewriting a little bit MSG, I could event speed it up a little
    bit more. Beside the gain in speed, it is also much easier to encode a
    new platform model with SURF than it was with SG. More to come...
  
  * REVOLUTION 3: I have tried to change a little as possible the API of
    MSG but a few things really had to disappear. The main differences
    with the previous version are :
       1) no more m_links_t and the corresponding functions. Platforms are
         directly read from a XML description and cannot be hard-coded
         anymore. The same format is used for application deployment
         description. The new format is described in the documentation. 
         Have a look in tools/platform_generation. There is a tiny script 
         that converts from the old platform format to the new one. Concerning
         the application deployment format, parsing the old one is tricky.  
         I think most of you should however be able to convert your files.  If 
         it is really an issue, I can write a C code that does the conversion. 
         Let me know.
       2) the toolbox tbx does not exist anymore. We now have a library
          with much more data-structures but without the hash-tables (we have 
          dictionaries that are much faster).

 -- Arnaud Legrand <Arnaud.Legrand@imag.fr>  Mon, 31 Jan 2005 10:45:53 -0800

*****************************************************************************
* Follows the old GRAS changelog. It does not follow the same syntax, but I *
* don't feel like converting the oldies. (Mt)                                *
*****************************************************************************

2005-01-31 Arnaud
  Version 2.90: "the long awaited one"
  - Finished rewriting and debugging MSG. Rewrote the documentation.
  - disable GRAS for now since it needs to be ported to the newest SG

2004-12-16 Martin
  - Finish the port to windows (using mingw32 for cross-compile)

2004-11-28 Arnaud
  - Main loop and datastructures of SURF. A cpu resource object is
    functional. Surf can thus be used to create cpu's with variable
    performance on which you can execute some actions.
        
2004-11-15 Martin Quinson
  - Port to ARM. Simply added the alignment and size descriptions. Should
    work, but the ARM machines are so slow that I didn't had the opportunity
    to 'make check' over there yet.

2004-11-15 Arnaud Legrand
  - Trace manager now written. It uses a heap structure and is therefore
    expected to be efficient. It may however be speeded up (particularly
    when many events occur at the same date) by using red and black
    trees. One day maybe... 
  - Max-min linear system solver written. It uses a sparse matrix
    structure taking advantage of its expected use. Most operations are
    O(1) and free/calloc are called as few as possible. The computation of
    the minimum could however be improved by using a red and black tree
    (again ! ;).

2004-11-03 Arnaud Legrand
  - Rename every gras_* function that was in xbt/ to its xbt_
    counterpart.
  - Add a heap and a doubly-linked list to xbt
  - Added a dichotomy to the dictionaries. make check works as well before
    so I assume that the patch is correct. I do not know however if things
    run effectively faster than before now. :)

  Inclusion of the SimGrid tree in the GRAS one. The archive is renamed to
  SimGrid, and the version number is bumped to 2.x

2004-10-29 Martin Quinson
  - Introduction of the remote errors. 
    They are the result of a RMI/RPC on the remote machine.
    ErrCodes being scalar values, you can't get the host on which those
    errors did happen. Extending the error mechanism as in Gnome is possible.
    No idea yet whether it is a good idea.
    
2004-10-28 Martin Quinson
  - Interface revolution: the Starred Structure Eradication.
    I used to do typedef struct {} toto_t; and then handle *toto_t.
    Arnaud (and Oli) didn't like it, and I surrendered. Now, you have:
      - ???_t is a valid type (builded with typedef)
      - s_toto_t is a structure (access to fields with .)
      - s_toto   is a structure needing 'struct' keyword to be used
      - e_toto_t is an enum
      -   toto_t is an 'object' (struct*)
    Exemple:
      typedef struct s_toto {} s_toto_t, *toto_t;
      typedef enum {} e_toto_t;
    Moreover, only toto_t (and e_toto_t) are public. The rest (mainly
     s_toto_t) is private.
    
  - While I was at it, all gras_<obj>_free() functions want a gras_<obj>_t*
    so that it can set the variable to NULL. It was so for dicts and sets,
    it changed for dynars.
    
  - Fix a bunch of memleaks in dict_remove
  - Fix a bug in sg/server_socket opening: it failed all the time.

2004-10-07 Martin Quinson
  - Speed up dynar lookup operation a bit.
  
    gras_dynar_get is dead. 
    
    Now, you can choose between gras_dynar_get_cpy (the old gras_dynar_get
    but should be avoided for efficiency reasons) and gras_dynar_get_ptr
    (which gives you the address of the stored data).
    
    gras_dynar_get_as is an helpful macro which allows you to retrieve a
    copy of the data using an affectation to do the job and not a memcpy.
    
    int toto = gras_dynar_get_as(dyn,0,int); rewrites itself to
    int toto = *(int*)gras_dynar_get_ptr(dyn,0);
    
    It does not really speedup the dynar test because they are
    setting elements all the time (and look them seldom). But the dict does
    far more lookup than setting.

    So, this brings the dict_crash test from ~33s to ~25s (200000 elms).

2004-10-05 Martin Quinson
  - Allow to (en/dis)able the cycle detection at run time.
  
    Whether we should check for cycle or not is now a property of each
    datatype. When you think there may be some cycle, use datadesc_cycle_set.
    datadesc_cycle_unset allow to remove this property when previously set.
    
    Note that the cycle detection is off by default since it impacts the 
    performance. Watch the data you feed GRAS with ;)
    
    This property is hereditary. Any element embedded in a structure having it
    set have it set for the time of this data exchange.
    
    You should set it both on sender and receiver side. If you don't set it on
    sender side, it will enter an endless loop. If you forget on receiver
    side, the cycles won't be recreated after communication.
    
  - Header reorganization.
    Kill gras_private.h, each submodule must load the headers it needs.

2004-10-04 Martin Quinson
  - Interface revolution: do not try to survive to malloc failure.
  
    Now, gras_malloc and friends call gras_abort() on failure.
    As a conclusion, malloc_error is not a valid error anymore, and all
      functions for which it was the only gras_error_t return value are
      changed. They now return void, or there result directly. 
    This simplify the API a lot.

2004-09-29 Martin Quinson
  - Re-enable raw sockets.
    Created by gras_socket_{client,server}_ext;
    Used with gras_raw_{send,recv}
    No select possible.
    
    It should allow to kill the last bits of gras first version soon.
  
    This is not completely satisfactory yet (duplicate code with
     chunk_{send,recv}; a bit out of the plugin mechanism), but it should
     work. 

  - Simplify transport plugin (internal) interface by not passing any
    argument to _server and _client, but embedding them in the socket
    struct directly. 

2004-09-28 Martin Quinson
  - Finish the port to AIX.
    autoconf was my problem (segfault within the malloc replacement
    function. No idea why)
        
2004-09-16 Martin Quinson
  - Fix some size_t madness on 64bit architectures.
  
2004-09-08 Martin Quinson
  - Reduce the number of system headers loaded, overload some more system
    calls (such as malloc to cast the result of the system one, and work
    properly on AIX)
  - Fix and reintroduce the config support

2004-09-07 Martin Quinson
  - Source code reorganization to allow Arnaud to surf all over there.
  - Allow to document the logging categories.
  - Remove all uppercase from logging categories and useless cleanup in names.

2004-08-18 Martin Quinson
  Version 0.6.2 (protocol not changed; API changed)
  - Interface cleanup: gras_msgtype_by_name returns the type (instead of a
     gras_error_t), and NULL when not found. Functions expecting a msgtype
     as argument (msg_wait; msg_send) deal with NULL argument by providing a
     hopefully usefull message.
  - Portability to prehistoric sparcs again

2004-08-17 Martin Quinson
  Version 0.6.1 (protocol not changed; ABI not changed)
  - prealloc some buffers to speed things up

2004-08-11 Martin Quinson
  Version 0.6 (protocol not changed; ABI expended)
  - The parsing macro can deal with the references, provided that you add
    the relevant annotations (using GRAS_ANNOTE(size,field_name))

2004-08-09 Martin Quinson
  Version 0.5 (protocol not changed; ABI changed)
  - Allow to off turn the cycle detection code in data exchange at
    compilation time. It should be at run time, but I'm short of time (and
    the config stuff is still broken). That way, we keep dict out of the
    critical path, which is good because the performance is poor:
     - search not dichotomial yet
     - dynar give no way to access their content and memcpy everytime
  - In composed data description (struct, ref and so on), stop foolness of
    keeping the subtype's ID, but store the type itself. This keeps sets out
    of the critical path, which is good since they rely on dynar and
    dictionnaries. The only loose of that is that we cannot detect the
    redeclaration of a structure/union with another content (but I'm not sure 
    the code detected well this error before anyway). We still can detect
    the redefinition discrepancy for the other types.
  - Use a whole bunch of optimisation flags (plus -fno-strict-aliasing since
    it breaks the code because of type-punning used all over the place).
    This breaks on all non-gcc architectures (for now).
    
  All those changes (plus the buffer of last time) allow me to gain 2 order
  of magnitude on cruel tests consisting of 800000 array of integers on two
  level of a hierarchical structure (200 secondes -> 4 secondes)
  
  API change:
    - the selector of reference must now return the type it points to, not
      the ID of this type.

2004-08-06 Martin Quinson
  Version 0.4 (protocol changed; ABI not changed)
  - Allow to pass --gras-log argument to processes in simulation mode. Really.
  - New debugging level: trace (under debug) to see effect of GRAS_IN/OUT
  - Implement a buffer transport, and use it by default (it relies on tcp in
     real life and on sg in simulation).
    That's a bit hackish since I had a new field to the structure to store
     its data without interfering with the subtype ones. Inheritance
     is tricky in C. And that's a kind of reverse inheritance with one class
     derivating two classes. Or maybe a game with java interfaces. Anyway,
     that's damn hard in C (at least).
    Moreover, I got tired while trying to ensure plugin separation and
     genericity in SG mode. MSG wants me to do weird things, so let's go for
     cruel hacks (temporarily of course ;).
     See comment in transport_private.h:71
  - do not include all the _interface headers in private but in the files
    which really need them (to cut the compilation time when they are
    modified) 

2004-07-26 Martin Quinson
  Version 0.3 (protocol not changed; ABI changed)
  - Major overhault of the datadesc interface to simplify it:
    - shorted the function names:
      s/gras_datadesc_declare_struct/gras_datadesc_struct/ and so on
    - add a trivial way to push/pop integers into the cbps without malloc.
      This allows to make really generic sub_type description, which simply
        pop their size of the stack.
    - add a function gras_datadesc_ref_pop_arr() which does what users want
      most of the time: Declare a dynamic array (which pops its size of the
      stack) and declare a reference to it. Poor name, but anyway.
    - kill the post-send callback, add a post-receive one
    
2004-07-23 Martin Quinson
  Version 0.2 (protocol changed; ABI changed)
  - add some testing for cpbs in the test cases, and fix some more bugs.
    This invalidate again the little64 data file, since I cannot regenerate
    it myself.
  - remove an awfull optimization in the logging stuff, allowing me to:
    - understand it again
    - learn gcc how to check that the argument match the provided format
    - fix all errors revealed by gcc after that
  - internal keys of dict are not \0 terminated. Deal with it properly in
    loggings instead of segfaulting when the user want to see the logs :-/

2004-07-22 Martin Quinson
  - Fix some stupid bug preventing cbps (callback postit) from working

2004-07-21 Martin Quinson
  - Some documentation cleanups
  - remove the useless last argument of msgtype_declare
  - rename the Virtu functions to fit into the 'os' namespace
  - move headers src/include -> src/include/gras/ and stop fooling with 
    gras -> . symbolic link
  - make distcheck is now successful

2004-07-19 Martin Quinson
  Version 0.1.1
  - Build shared library also
  - Install html doc to the right location
  - stop removing maintainer files in make clean
  - build tests only on make check
  
2004-07-13 Martin Quinson
  version 0.1
  - No major issue in previous version => change versionning schema
  - Re-enable little64 convertion test now that Abdou kindly regenerated the
    corresponding dataset.
  
2004-07-11 Martin Quinson
  version 0.0.4
  - Get it working with any kind of structure (we can compute the padding
    bytes remotely for all the architectures I have access to)
  - Implement the structure parsing macro (still not quite robust/complete)
  - Improvement to the remote testing toysuite
  
2004-07-10 Martin Quinson
 [autoconf mechanism]
  - get ride of a bunch of deprecated macros
  - actually run the test for two-compliment, not only compile it :-/
  - test whether the structures get packed (and bail out if yes. Damn.
    Alignment is a serious matter)
  - test whether the structures get compacted (but respecting the alignment
    constraints of each types)
  - test whether the array fields of structures can straddle alignment boundaries
 [base]
  - Damnit, double are bigger than float (typo in creation of 'double' datadesc)
    (took me 2 hours to find that bug, looking at the wrong place)
  - Add gras_datadesc_declare_{union,struct}_close(). They must be used
    before sending/receiving and are used to compute the offsets of fields
  - Given that padding size depend even on compiler options, keep track of
    alignment and aligned_size only for the current architecture. Not a big
    deal since we send structure fields one after the other (seems
    reasonable).    
  - Add the datastructure used for IEEE paper by the PBIO guys to the test
    program, let it work on linux/gcc/little32. portability todo.

2004-07-08 Martin Quinson
  - import and improve remote compilation support from FAST
  - make sure make check works on half a dozen of machines out there

2004-07-07 Martin Quinson
 Let's say it's version 0.0.3 ;)
  - Implement conversions (yuhu!)
  - Let it work on solaris (beside conversion, of course)
  - Stupid me, using rand() to generate the conversion datatests in not wise.

2004-07-06 Martin Quinson
  - Let make dist work, since I'm gonna need it to compile on remote hosts
  - Let Tests/datadesc_usage write the architecture on which the file was
    generated as first byte.
  - Add PowerPC (being also IRIX64), SPARC (also power4) and ALPHA
    architecture descriptions. 
  - Add datadesc_usage.{i386,ppc,sparc} files being the result of execution
    on those architectures.
  - Optimization: send/recv array of scalar in one shoot

2004-07-05 Martin Quinson
  - YEAH! GRAS/SG and GRAS/RL are both able to run the ping example !
  
  - Plug a whole bunch of memleaks
  - each process now have to call gras_{init,exit}. One day, their log
    settings will be separated
  - Continue the code factorisation between SG, RL and common in Transport.

2004-07-04 Martin Quinson
 [Transport]
  - Redistribution between SG and RL. 
    We wanna have to accept in SG, so move accepted related parts of RL in
    the common part. (more precisely, the dynar of all known sockets is no
    more a static in transport.c, but part of the process_data)
 [Core/module.c] 
 [gras_stub_generator]
  - Bug fix: Do call gras_process_init from gras_init (wasnt called in RL).

2004-07-03 Martin Quinson
  - Create a new log channel tbx containing dict, set, log, dynar (to shut
    them all up in one shot)
 [DataDesc]
  - Fix the ugly case of reference to dynamic array.
  - New (semi-public) function gras_datadesc_size to allow the messaging
    layer to malloc the needed space for the buffer.
 [Transport]
  - gras_socket_close now expect the socket to close (and not its address to
    put NULL in it after it). This is because the socket passed to handlers
    is one of their argument (=> not writable).
 [Messaging]
  - propagate the interface cleanup from last week in datadesc, ie remove a
    superfluous level of indirection. User pass adress of variable
    containing data (both when sending and receiving), and not of a variable
    being a pointer to the data. Let's say that I like it better ;)
      The price for that is constructs like "int msg=*(int*)payload" in
    handlers, but it's a fine price, IMHO.
 [examples/ping]
  - Let it work in RL (yuhu)

2004-06-21 Martin Quinson
 [Transport]
   - porting SG plugin and SG select to new standards (works almost).
   - plug memleaks and fix bugs around.
   
 [DataDesc] 
   - cleanup the prototype of data recv and force users to specify when they 
     want to handle references to objects. Test case working even for cycles.
   - plug memleaks. Valgrind is perfectly ok with this.

2004-06-12 Martin Quinson
 [Transport] 
   - cleanup the separation between plugin and main code in plugin creation 

2004-06-11 Martin Quinson
 [Transport]
   - Reput hook for raw sockets, needed for BW experiments
   - kill a few lines of dead code
 [Data description] Interface cleanup
   - gras_datadesc_by_name returns the searched type or NULL.
     That way, no variable is needed to use a type desc once, which makes
      the code clearer.
   - gras_datadesc_declare_[struct|union]_append_name is removed. The last
      two parameters were strings (field name, type name), leading to
      common errors.
 [Dicos] Interface cleanup
   - gras_dico_retrieve -> gras_dico_get ; gras_dico_insert -> gras_dico_set 
     This is consistant with the dynar API.

2004-04-21 Martin Quinson
 [Messaging]
   - Porting to new standards.
 [Data description]
   - interface cleanup. 
     There is no bag anymore, no need to take extra provision to mask the
       pointers behind "ID". 
     Better splitup of functions between files create/exchange/convert.
       This is still a bit artificial since convert and receive are so
       interleaved, but anyway.
 [Virtu(process)]
   - add a queued message list to procdata (the ones not matching criteria
     in msg_wait)
   - factorize some more code between SG and RL wrt procdata
 [Tests]
   - use gras_exit in example to track memleaks
   - get rid of gs_example now that GS is properly integrated into gras
   - update run_test to integrate the lastest tests (datadesc)
 [Logging]
   - rename WARNINGn macros to WARNn since it prooved error-prone
     
2004-04-19 Martin Quinson
 [Data description]
   - register init/exit functions within gras module mechanism   
   - send/receive function. 
   Convertion is not implemented, but short-cutted if not needed.
   struct/array elements are sent one by one (instead of block-wise), but
     nobody really cares (yet). Get a prototype before optimizing.
   - tests (using a file socket) for DD send/receive on:
     - base types: int, float
     - array: fixed size, string (ie ref to dynamic string)
     - structure: homogeneous, heterogeneous
     - chained list, graph with cycle
   Believe it or not, valgrind is not too unhappy with the results. The
    cycle happily segfaults, but the others are ok. And I'm sick of pointers
    for now.
 [Transport]
   [File plugin] 
     - Bugfix when using a filename explicitely (instead of '-')

2004-04-09 Martin Quinson
 [Transport plugins]
   - factorize more code between RL and SG in socket creation
   - Complete the implementation and tests of:
     o TCP
     o file (only in RL, and mainly for debugging)
     
     I lost 3 days to design a portable address resolver, and then decided
       that the prototype mainly have to run on my box.
     Addressing portability too early may be like optimizing too early :-/
 [Tests]
   - use gras_init in the Tests instead of the crappy parse_log_opt 
     (the latter function is removed)
 [Conditional execution]
   - New functions: gras_if_RL/gras_if_SG (basic support for this)
 [Code reorganisation]
  - Get rid of libgrasutils.a since it makes more trouble than it solves.
    Build examples against the RL library, since there is no way to disable
    its creation for now.