Keeping the cache misses as low as possible is always a good approach.
The opal_list_t is widely used, it should be a highly optimized class.
The same functionality can be reached with one one sentinel instead
of 2 currently used.
I don't have anything against the STL version, but so far nothing can
compare with the Knuth algorithm. I replace the current implementation
with a modified version of the Knuth algorithm (the one described in
The Art of Computer Programming). As expected, the latency went down.
This commit was SVN r10776.
was smaller than the CACHE_LINE_SIZE. Here is the version that works.
In fact this works on 2 steps. First we set the element size to something
multiple of the desired alignment. Then when we allocate memory, we compute
the total size, and we will align each of the elements (we allocate
multiple of them every time) to the CACHE_LINE_SIZE.
This commit was SVN r10479.
bytes). The simplest way to make sure they are aligned is to update
the size of the basic element to a multiple of the desired alignment.
It will use a little bit more memory, but the improvements on the SM BTL
seems quite interesting.
This commit was SVN r10478.
free list. It use the size attached to the free list, and the internal
memory segments to find out all the items allocated by this free list.
This commit was SVN r9669.
The free lst using atomic operations. I didn't want to completely
change the behavior, so we still use a mutex for the extreme cases (like
no more available items and we cannot allocate more). I test it for a
while on non multi-threading environment, but not enough on a multi-threaded
build.
This commit was SVN r9623.
flag, new flags to be included when convertor is initialized
- modified pml/btl module defs and added stub functions for diagnostic
output routines to dump state of queues / endpoints
- updates to data reliability pml
This commit was SVN r9329.
- move files out of toplevel include/ and etc/, moving it into the
sub-projects
- rather than including config headers with <project>/include,
have them as <project>
- require all headers to be included with a project prefix, with
the exception of the config headers ({opal,orte,ompi}_config.h
mpi.h, and mpif.h)
This commit was SVN r8985.
- remove dead code that isn't used anywhere (originally ompi_fifo_t
was going to be a generalized class, but now it's exclusively used
in the sm stuff, so there's no point in the generalized code that
definitely *won't* work with the sm btl, or is not being used now
[SVN always has history so we can go back])
- had to add an interprocess lock in the area where the writer may
create a new circular buffer to ensure that the reader's tail
doesn't accidentally end up back in the same old buffer while the
head continues on to a new circular buffer (this was what was
happening to cause some intel tests to hang -- e.g., MPI_Scan_c,
MPI_Send_fairness_c and MPI_Isend_fairness_c). Unbelievably, this
may actually *increase* performance because it may order things
better. Will do performance testing tomorrow. We're fairly certain
that this lock can probably be removed and the code fixed in a
different way, but we're under a deadline and correctness comes
first, so it's been added to the to-do list to come back and
re-examine this case later.
This commit was SVN r8136.
- Add big comment about a general overview of what the sm btl is doing
- random small code cleanups
- fix instances of mca_btl_sm[0] to mca_btl_sm[1] where relevant
- remove a lot of unused, confusing, and incorrect interface functions
from ompi_fifo.h and ompi_circular_buffer.h. These functions, if
they were used, would not work properly with the scheme that the sm
btl uses with the fifos (i.e., receiver makes right -- if necessary)
- add some missing offset computations in the fifo and circular buffers
- change the types of offsets to be ssize_t, not size_t
- remove an offset parameter from a function that didn't need it
This commit was SVN r8135.
originally suggested by Ralf Wildenhues, to try to speed autogen, configure,
and make (and possibly even make install). Use automake's include directive
to drastically reduce the number of Makefile files (although the number of
Makefile.am files is the same - most are just included in a top-level
Makefile.am). Also use an Automake SUBDIRs feature to eliminate the
dynamic-mca tree, which was no longer really needed. This makes adding
a framework easier (since you don't have to remember the dynamic-mca
tree) and makes building faster (as make doesn't have to recurse through
the dynamic-mca tree)
This commit was SVN r7777.
- corrected memory hook callback to catch all allocations (need to optimize this)
- don't attempt to consolidate allocations
This commit was SVN r7600.
AM_INIT_AUTOMAKE, instead of the deprecated version.
* Work around dumbness in modern AC_INIT that requires the version
number to be set at autoconf time (instead of at configure time, as
it was before). Set the version number, minus the subversion r number,
at autoconf time. Override the internal variables to include the r
number (if needed) at configure time. Basically, the right thing
should always happen. The only place it might not is the version
reported as part of configure --help will not have an r number.
* Since AM_INIT_AUTOMAKE taks a list of options, no need to specify
them in all the Makefile.am files.
* Addes support for subdir-objects, meaning that object files are put
in the directory containing source files, even if the Makefile.am is
in another directory. This should start making it feasible to
reduce the number of Makefile.am files we have in the tree, which
will greatly reduce the time to run autogen and configure.
This commit was SVN r7211.
- move mpool and allocator frameworks back to ompi (from opal)
- specialize the ompi_free_list class to use an mpool instance
- un-specialize opal_free_list to *not* use mpool; just use malloc/free
This commit was SVN r6292.
