Reset steps before reading the rankTable

openPMD · Jan 14, 2025 · 82eea7a · 82eea7a
1 parent d5ca329
commit 82eea7a
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Showing 6 changed files with 34 additions and 7 deletions.
diff --git a/include/openPMD/IO/ADIOS/ADIOS2File.hpp b/include/openPMD/IO/ADIOS/ADIOS2File.hpp
@@ -413,7 +413,7 @@ class ADIOS2File
     StreamStatus streamStatus = StreamStatus::OutsideOfStep;
 
     size_t currentStep();
-    void setStepSelection(size_t);
+    void setStepSelection(std::optional<size_t>);
     [[nodiscard]] std::optional<size_t> stepSelection() const;
 
 private:

diff --git a/include/openPMD/IO/IOTask.hpp b/include/openPMD/IO/IOTask.hpp
@@ -672,7 +672,7 @@ struct OPENPMDAPI_EXPORT Parameter<Operation::ADVANCE>
 
     struct StepSelection
     {
-        size_t step;
+        std::optional<size_t> step;
     };
 
     //! input parameter

diff --git a/src/IO/ADIOS/ADIOS2File.cpp b/src/IO/ADIOS/ADIOS2File.cpp
@@ -353,16 +353,24 @@ size_t ADIOS2File::currentStep()
     }
 }
 
-void ADIOS2File::setStepSelection(size_t step)
+void ADIOS2File::setStepSelection(std::optional<size_t> step)
 {
     if (streamStatus != StreamStatus::ReadWithoutStream)
     {
         throw error::Internal(
             "ADIOS2 backend: Cannot only use random-access step selections "
             "when reading without streaming mode.");
     }
-    m_currentStep = step;
-    useStepSelection = true;
+    if (!step.has_value())
+    {
+        m_currentStep = 0;
+        useStepSelection = false;
+    }
+    else
+    {
+        m_currentStep = *step;
+        useStepSelection = true;
+    }
 }
 
 std::optional<size_t> ADIOS2File::stepSelection() const

diff --git a/src/IO/AbstractIOHandlerImpl.cpp b/src/IO/AbstractIOHandlerImpl.cpp
@@ -421,7 +421,11 @@ std::future<void> AbstractIOHandlerImpl::flush()
                                 [](Parameter<Operation::ADVANCE>::StepSelection
                                        step) {
                                     std::stringstream s;
-                                    s << "RANDOMACCESS '" << step.step << "'";
+                                    s << "RANDOMACCESS '"
+                                      << (step.step.has_value()
+                                              ? std::to_string(*step.step)
+                                              : std::string("RESET"))
+                                      << "'";
                                     return s.str();
                                 }},
                             parameter.mode);

diff --git a/src/Series.cpp b/src/Series.cpp
@@ -256,6 +256,14 @@ chunk_assignment::RankMeta Series::rankTable([[maybe_unused]] bool collective)
         rankTable.m_bufferedRead = chunk_assignment::RankMeta{};
         return {};
     }
+    if (iterationEncoding() == IterationEncoding::variableBased &&
+        IOHandler()->m_backendAccess == Access::READ_RANDOM_ACCESS)
+    {
+        Parameter<Operation::ADVANCE> advance;
+        advance.mode =
+            Parameter<Operation::ADVANCE>::StepSelection{std::nullopt};
+        IOHandler()->enqueue(IOTask(this, std::move(advance)));
+    }
     Parameter<Operation::OPEN_DATASET> openDataset;
     openDataset.name = "rankTable";
     IOHandler()->enqueue(IOTask(&rankTable.m_attributable, openDataset));

diff --git a/test/SerialIOTest.cpp b/test/SerialIOTest.cpp
@@ -5246,7 +5246,8 @@ void serial_iterator(std::string const &file)
 {
     constexpr Extent::value_type extent = 1000;
     {
-        Series writeSeries(file, Access::CREATE);
+        Series writeSeries(
+            file, Access::CREATE, "rank_table = \"posix_hostname\"");
         auto iterations = writeSeries.writeIterations();
         for (size_t i = 0; i < 10; ++i)
         {
@@ -5277,6 +5278,12 @@ void serial_iterator(std::string const &file)
         }
         last_iteration_index = iteration.iterationIndex;
     }
+    if (readSeries.iterationEncoding() == IterationEncoding::variableBased)
+        for (auto const &[rank, host] : readSeries.rankTable(true))
+        {
+            std::cout << "POST Rank '" << rank << "' written from host '"
+                      << host << "'\n";
+        }
     REQUIRE(last_iteration_index == 9);
     REQUIRE(numberOfIterations == 10);
 }