Make maximum number of C API copies configurable

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/copying/NativeLibraryLocator.java

@@ -42,12 +42,14 @@
 
 import static com.oracle.graal.python.nodes.StringLiterals.J_NATIVE;
 import static com.oracle.graal.python.nodes.StringLiterals.T_BASE_PREFIX;
+import static com.oracle.graal.python.nodes.StringLiterals.J_MAX_CAPI_COPIES;
 import static com.oracle.graal.python.nodes.StringLiterals.T_PREFIX;
 import static com.oracle.graal.python.util.PythonUtils.toTruffleStringUncached;
 
 import java.io.IOException;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import com.oracle.graal.python.PythonLanguage;
 import com.oracle.graal.python.builtins.objects.cext.common.LoadCExtException.ApiInitException;
 import com.oracle.graal.python.builtins.objects.cext.common.LoadCExtException.ImportException;
 import com.oracle.graal.python.nodes.ErrorMessages;
@@ -58,6 +60,7 @@
 import com.oracle.graal.python.util.BiFunction;
 import com.oracle.truffle.api.TruffleFile;
 import com.oracle.truffle.api.TruffleLanguage.Env;
+import com.oracle.truffle.api.TruffleLogger;
 
 /**
  * Given a GraalPy virtual environment, this class helps prepare that environment so that multiple
@@ -67,7 +70,9 @@
  * guaranteed to work with the matching GraalPy version.
  */
 public final class NativeLibraryLocator {
-    private static final int MAX_CEXT_COPIES = 64;
+    static final TruffleLogger LOGGER = PythonLanguage.getLogger("NativeLibraryLocator");
+
+    private static final int MAX_CEXT_COPIES = Integer.getInteger(J_MAX_CAPI_COPIES, 64);
 
     /**
      * Bitset for which copied C extension to use when {@link PythonOptions#IsolateNativeModules} is
@@ -144,6 +149,11 @@ public void close() {
      * count}.
      */
     public static void replicate(TruffleFile venvDirectory, PythonContext context, int count) throws IOException, InterruptedException {
+        if (count > MAX_CEXT_COPIES) {
+            LOGGER.warning(() -> String.format("The current limit for concurrent Python contexts accessing the Python C API is %d, " +
+                                            "but we are preparing %d copies. The extra copies will only be used if a different value " +
+                                            "of the system property %s is set.", MAX_CEXT_COPIES, count, J_MAX_CAPI_COPIES));
+        }
         String suffix = context.getSoAbi().toJavaStringUncached();
         TruffleFile capiLibrary = context.getPublicTruffleFileRelaxed(context.getCAPIHome()).resolve(PythonContext.getSupportLibName("python-" + J_NATIVE));
         try {

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/copying/SharedObject.java

@@ -43,7 +43,6 @@
 import java.io.IOException;
 import java.io.OutputStream;
 
-import com.oracle.graal.python.PythonLanguage;
 import com.oracle.graal.python.runtime.PythonContext;
 import com.oracle.truffle.api.TruffleFile;
 import com.oracle.truffle.api.TruffleLogger;
@@ -72,7 +71,7 @@ static SharedObject open(TruffleFile file, PythonContext context) throws IOExcep
         }
     }
 
-    protected static final TruffleLogger LOGGER = PythonLanguage.getLogger("NativeLibraryLocator");
+    protected static final TruffleLogger LOGGER = NativeLibraryLocator.LOGGER;
 
     protected static final class LoggingOutputStream extends OutputStream {
         private final StringBuilder sb = new StringBuilder();
@@ -88,8 +87,8 @@ public void write(byte[] b, int off, int len) throws IOException {
         }
 
         @Override
-        public void flush() throws IOException {
-            LOGGER.fine(() -> sb.toString());
+        public void flush() {
+            LOGGER.fine(sb::toString);
             sb.setLength(0);
         }
     }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/ErrorMessages.java

@@ -41,6 +41,7 @@
 package com.oracle.graal.python.nodes;
 
 import static com.oracle.graal.python.builtins.objects.str.StringUtils.cat;
+import static com.oracle.graal.python.nodes.StringLiterals.J_MAX_CAPI_COPIES;
 import static com.oracle.graal.python.util.PythonUtils.tsLiteral;
 
 import com.oracle.graal.python.builtins.PythonOS;
@@ -1672,7 +1673,7 @@ public abstract class ErrorMessages {
     public static final TruffleString SYS_PREFIX_MUST_BE_STRING_NOT_P_FOR_CAPI_ISOLATION = tsLiteral("The sys.prefix must be a str, not '%p' when the `IsolateNativeModules' option is used, because it is the base path for searching the relocated C API. Refer to https://www.graalvm.org/latest/reference-manual/python/Native-Extensions for details on native module isolation.");
     public static final TruffleString SYS_PREFIX_MUST_POINT_TO_A_VENV_FOR_CAPI_ISOLATION = tsLiteral("The sys.prefix must point to a venv, not be identical to sys.base_prefix when the `IsolateNativeModules' option is used, because it is the base path for searching and creating the relocated C API and extension modules. Refer to https://www.graalvm.org/latest/reference-manual/python/Native-Extensions for details on native module isolation.");
     public static final TruffleString CAPI_ISOLATION_CAPPED_AT_D = tsLiteral(
-                    "There is no available slot for C API isolation. The current limit for concurrent Python contexts accessing the Python C API is %d.");
+                    "There is no available slot for C API isolation. The current limit for concurrent Python contexts accessing the Python C API is %d. This can be changed with the" + J_MAX_CAPI_COPIES + " System property.");
     public static final TruffleString SYS_PREFIX_MUST_BE_STRING_NOT_P_FOR_CAPI_ISOLATION = tsLiteral(
                     "The sys.prefix must be a str, not '%p' when the `IsolateNativeModules' option is used, because it is the base path for searching the relocated C API. " +
                                     "Refer to https://www.graalvm.org/latest/reference-manual/python/Native-Extensions for details on native module isolation.");

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/StringLiterals.java

@@ -160,4 +160,5 @@ public abstract class StringLiterals {
     public static final TruffleString T_VISIT = tsLiteral("visit");
     public static final TruffleString T_PREFIX = tsLiteral("prefix");
     public static final TruffleString T_BASE_PREFIX = tsLiteral("base_prefix");
+    public static final String J_MAX_CAPI_COPIES = "python.MaximumNumberOfCextCopies";
 }