Merge pull request #1663 from garlick/nix_pmix

libpmi: drop pmix client support and --with-pmix configure option

.travis.yml

@@ -9,15 +9,15 @@ matrix:
     - compiler: clang
       env: LUA_VERSION=5.1
     - compiler: gcc
-      env: LUA_VERSION=5.1 COVERAGE=t ARGS="--with-flux-security --with-pmix --enable-caliper --enable-pylint"
+      env: LUA_VERSION=5.1 COVERAGE=t ARGS="--with-flux-security --enable-caliper --enable-pylint"
     - compiler: gcc
       env: LUA_VERSION=5.1 T_INSTALL=t
     - compiler: clang
-      env: LUA_VERSION=5.1 CPPCHECK=t ARGS="--with-flux-security --with-pmix --enable-sanitizer" CC=clang-3.8 CXX=clang++-3.8
+      env: LUA_VERSION=5.1 CPPCHECK=t ARGS="--with-flux-security --enable-sanitizer" CC=clang-3.8 CXX=clang++-3.8
     - compiler: gcc
-      env: LUA_VERSION=5.2 CC=gcc-8 CXX=g++-8 ARGS="--with-flux-security --with-pmix" chain_lint=t
+      env: LUA_VERSION=5.2 CC=gcc-8 CXX=g++-8 ARGS="--with-flux-security" chain_lint=t
     - compiler: clang
-      env: LUA_VERSION=5.2 ARGS="--with-flux-security --with-pmix --enable-caliper" CC=clang-3.8 CXX=clang++-3.8
+      env: LUA_VERSION=5.2 ARGS="--with-flux-security --enable-caliper" CC=clang-3.8 CXX=clang++-3.8
 
 cache:
   directories:
@@ -47,7 +47,6 @@ addons:
       - valgrind
       - libyaml-cpp-dev
       - libboost-dev # for yaml-cpp 0.5.1. >=0.5.2 no longer need boost
-      - libevent-dev # pmix needs this
 
   coverity_scan:
     project:

README.md

@@ -129,3 +129,24 @@ Common commands from flux-core:
 
 Most of these have UNIX manual pages as `flux-<sub-command>(1)`,
 which can also be accessed using `./flux help <sub-command>`.
+
+#### A note about PMI
+
+When flux is launched, it requires PMI-1 in order to bootstrap.
+It can use PMI-1 in one of two ways, by inheriting a file descriptor
+via the `PMI_FD` environment variable, or by dlopening a PMI library.
+The library name is `libpmi.so`, unless overridden by the `PMI_LIBRARY`
+environment variable.  If a PMI library is not found, flux falls back
+to "singleton" operation, where each broker is an independent flux instance.
+The PMI bootstrap may be traced by setting the `FLUX_PMI_DEBUG` environment
+variable.
+
+When flux launches flux or an MPI job, it provides PMI-1 to bootstrap the
+MPI's runtime.  It offers a PMI server and sets the `PMI_FD` environment
+variable to point to an open file descriptor connected to it.  It also offers
+a `libpmi.so` library that can be dlopened.
+
+If your system process manager uses PMIx, the `libpmi.so` compatibility library
+provided by the PMIx project should be sufficient to bootstrap flux.
+If your version of PMIx was not built with the compatibility libraries
+installed, you may build libpmix as a separate package to get them installed.

configure.ac

@@ -202,7 +202,6 @@ X_AC_JANSSON
 X_AC_YAMLCPP
 PKG_CHECK_MODULES([HWLOC], [hwloc >= 1.11.1], [], [])
 PKG_CHECK_MODULES([SQLITE], [sqlite3], [], [])
-X_AC_PMIX
 LX_FIND_MPI
 AM_CONDITIONAL([HAVE_MPI], [test "$have_C_mpi" = yes])
 AX_VALGRIND_H

src/common/libpmi/Makefile.am

@@ -32,12 +32,6 @@ libpmi_la_SOURCES = \
 	clique.h \
 	pmi_operations.h
 
-if HAVE_LIBPMIX
-libpmi_la_SOURCES += \
-	pmix_client.c \
-	pmix_client.h
-endif
-
 fluxinclude_HEADERS = \
 	pmi.h \
 	pmi2.h
@@ -56,7 +50,7 @@ test_ldadd = \
 	$(top_builddir)/src/common/liblsd/liblsd.la \
 	$(top_builddir)/src/common/libev/libev.la \
 	$(ZMQ_LIBS) $(JANSSON_LIBS) $(LIBPTHREAD) \
-	$(LIBRT) $(LIBDL) $(LIBMUNGE) $(LIBPMIX)
+	$(LIBRT) $(LIBDL) $(LIBMUNGE)
 
 test_cppflags = \
 	-I$(top_srcdir)/src/common/libtap \

src/common/libpmi/pmi.c

@@ -35,7 +35,6 @@
 #include "pmi.h"
 #include "pmi_strerror.h"
 #include "simple_client.h"
-#include "pmix_client.h"
 #include "wrap.h"
 #include "single.h"
 #include "clique.h"
@@ -82,15 +81,6 @@ int PMI_Init (int *spawned)
         if (!(ctx.impl = pmi_simple_client_create (&ctx.ops)))
             goto done;
     }
-#if HAVE_LIBPMIX
-    /* If PMIX_SERVER_* is set, pmix service is offered.
-     * Use the pmix client.
-     */
-    else if (getenv ("PMIX_SERVER_URI") || getenv ("PMIX_SERVER_URI2")) {
-        if (!(ctx.impl = pmix_client_create (&ctx.ops)))
-            goto done;
-    }
-#endif
     /* If PMI_LIBRARY is set, we are directed to open a specific library.
      */
     else if ((library = getenv ("PMI_LIBRARY"))) {