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openmpi/ompi/op
Ralph Castain 125d236173 Move from the use of regex to compression
We've been fighting the battle of trying to create a regex generator and
parser that can handle arbitrary hostname schemes - without long-term
success. The worst of it is that there is no way of checking to see if
the computed regex is correct short of parsing it and doing a
character-by-character comparison with the original string. Ugh...there
has to be a better solution.

One option is to investigate using 3rd-party regex libraries as
those are coming from communities whose sole focus is resolving that
problem. However, someone would need to spend the time to investigate
it, and we'd have to find a license-friendly implementation.

Another option is to quit beating our heads against the wall and just
compress the information. It won't be as much of a reduction, but we
also won't keep hitting scenarios where things break. In this case, it
seems that "perfection" is definitely the enemy of "good enough".

This PR implements the compression option while retaining the
possibility of people adding regex-generating components. The
compression code used in ORTE is consolidated into the opal/compress
framework. That framework currently held bzip and gzip components for
use in compressing checkpoint files - since we no longer support C/R, I
have .opal_ignore'd those components.

However, I have left the original framework APIs alone in case someone
ever decides to redo C/R. The APIs of interest here are added to the
framework - specifically, the "compress_block" and "decompress_block"
functions. I then moved the ORTE zlib compression code into a new
component in this framework.

Unfortunately, the framework currently is a single-select one - i.e.,
only one active component at a time. Since I .opal_ignore'd the other
two and made the priority of zlib high, this isn't a problem. However,
if someone wants to re-enable bzip/gzip or add another component, they
might need to transition opal/compress to a multi-select framework.

Included changes:

* Consolidate the compression code into the opal/compress framework

* Move the ORTE zlib compression code into a new opal/compress/zlib
  component

* Ignore the bzip and gzip components in opal/compress framework

* Add a "compress_base_limit" MCA param to set the threshold above which
  we compress data - defaults to 4096 bytes

* Delete stale brucks and rcd components from orte/grpcomm framework

* Delete the orte/regx framework

* Update the launch system to use opal/compress instead of string regex

* Provide a default module if no zlib is available

* Fix some misc multi-node issues

* Properly generate the nidmap in response to a "connection warmup"
  message so the remote daemon knows the children it needs to launch.

* Remove stale references to orte_node_regex

* opal_byte_object_t's are not OPAL objects - properly release allocated
  memory.

* Set the topology

* Currently only handling homogeneous case

* Update the compress framework files to conform

* Consolidate open/close into one "frame" file. Ensure we open/close the
  framework

Signed-off-by: Ralph Castain <rhc@pmix.org>
2019-02-08 11:11:14 -08:00
..
Makefile.am Revert "Update to sync with OMPI master and cleanup to build" 2016-11-22 15:03:20 -08:00
op.c ompi/datatype: Use short float for MPI_REAL2 2019-02-01 13:01:10 +09:00
op.h Move from the use of regex to compression 2019-02-08 11:11:14 -08:00