diff --git a/bin/mpi-fastspecfit b/bin/mpi-fastspecfit
index ba60e7e7..5f2ff15e 100755
--- a/bin/mpi-fastspecfit
+++ b/bin/mpi-fastspecfit
@@ -189,9 +189,12 @@ def run_fastspecfit(args, comm=None, fastphot=False, specprod_dir=None, makeqa=F
     #print(f'Rank={comm.rank}, subrank={subcomm.rank}, redrockfiles={redrockfiles}, ntargets={ntargets}')
 
     for redrockfile, outfile, ntarget in zip(redrockfiles, outfiles, ntargets):
-        if subcomm.rank == 0:
-            log.debug(f'Rank {rank} (subrank {subcomm.rank}) started ' + \
-                      f'at {time.asctime()}')
+        if subcomm:
+            if subcomm.rank == 0:
+                log.debug(f'Rank {rank} (subrank {subcomm.rank}) started ' + \
+                          f'at {time.asctime()}')
+        elif rank == 0:
+            log.debug(f'Rank {rank} started at {time.asctime()}')
 
         if args.makeqa:
             from fastspecfit.qa import fastqa as fast
@@ -204,15 +207,24 @@ def run_fastspecfit(args, comm=None, fastphot=False, specprod_dir=None, makeqa=F
         cmd, cmdargs, logfile = build_cmdargs(args, redrockfile, outfile, sample=sample,
                                               fastphot=fastphot, input_redshifts=input_redshifts)
 
-        if subcomm.rank == 0:
-            log.info(f'Rank {rank} (nsubrank={subcomm.size}): ' + \
-                     f'ntargets={ntarget}: {cmd} {cmdargs}')
+        if subcomm:
+            if subcomm.rank == 0:
+                log.info(f'Rank {rank} (nsubrank={subcomm.size}): ' + \
+                         f'ntargets={ntarget}: {cmd} {cmdargs}')
+        elif rank == 0:
+            log.info(f'Rank {rank}: ntargets={ntarget}: {cmd} {cmdargs}')
 
         if args.dry_run:
             continue
 
         try:
-            if subcomm.rank == 0:
+            if subcomm:
+                if subcomm.rank == 0:
+                    t1 = time.time()
+                    outdir = os.path.dirname(logfile)
+                    if not os.path.isdir(outdir):
+                        os.makedirs(outdir, exist_ok=True)
+            elif rank == 0:
                 t1 = time.time()
                 outdir = os.path.dirname(logfile)
                 if not os.path.isdir(outdir):
@@ -225,19 +237,31 @@ def run_fastspecfit(args, comm=None, fastphot=False, specprod_dir=None, makeqa=F
                     #log.info(f'rank={comm.rank} subrank={subcomm.rank}')
                     err = fast(args=cmdargs.split(), comm=subcomm)
 
-            if subcomm.rank == 0:
+            if subcomm:
+                if subcomm.rank == 0:
+                    dt1 = time.time() - t1
+                    log.info(f'  rank {rank} done in {dt1:.2f} sec')
+                    if err != 0:
+                        if not os.path.exists(outfile):
+                            log.warning(f'  rank {rank} missing {outfile}')
+                            raise IOError
+            elif rank == 0:
                 dt1 = time.time() - t1
                 log.info(f'  rank {rank} done in {dt1:.2f} sec')
                 if err != 0:
                     if not os.path.exists(outfile):
                         log.warning(f'  rank {rank} missing {outfile}')
                         raise IOError
+
         except:
             log.warning(f'  rank {rank} raised an exception')
             import traceback
             traceback.print_exc()
 
-    if subcomm.rank == 0:
+    if subcomm:
+        if subcomm.rank == 0:
+            log.debug(f'  rank {rank} is done')
+    elif rank == 0:
         log.debug(f'  rank {rank} is done')
 
     if comm:
@@ -322,11 +346,9 @@ def main():
     else:
         try:
             from mpi4py import MPI
-            MPI.Init_thread(MPI.THREAD_SINGLE)
             # needed when profiling; no effect otherwise
             # https://docs.linaroforge.com/24.0.6/html/forge/map/python_profiling/profile_python_script.html
-            mpi4py.rc.threaded = False
-            #mpi4py.rc.thread_level = "funneled"
+            #MPI.Init_thread(MPI.THREAD_SINGLE)
             comm = MPI.COMM_WORLD
         except ImportError:
             comm = None