Modified script to commit smaller batches of symbols to the database.

Summary:
Modified the import script so it will only try to load a configurable
number of symbols at a time to avoid exhausting memory for large project
imports.

I haven't written a line of PHP in more than a decade, so please forgive
any stylistic or technical errors.

Test Plan: Ran the script on symbol table generated from linux kernel.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Maniphest Tasks: T4117

Differential Revision: https://secure.phabricator.com/D7596

scripts/symbols/import_project_symbols.php

@@ -1,6 +1,7 @@
 #!/usr/bin/env php
 <?php
 
+
 $root = dirname(dirname(dirname(__FILE__)));
 require_once $root.'/scripts/__init_script__.php';
 
@@ -24,6 +25,13 @@ $args->parse(
       'help'      => 'If a line can\'t be parsed, ignore that line and '.
                      'continue instead of exiting.',
     ),
+    array(
+      'name'      => 'max-transaction',
+      'param'     => 'num-syms',
+      'default'  => '100000',
+      'help'      => 'Maximum number of symbols that should '.
+                     'be part of a single transaction',
+    ),
     array(
       'name'      => 'more',
       'wildcard'  => true,
@@ -53,6 +61,52 @@ $input = file_get_contents('php://stdin');
 $input = trim($input);
 $input = explode("\n", $input);
 
+
+function commit_symbols ($syms, $project, $no_purge) {
+  echo "Looking up path IDs...\n";
+  $path_map =
+    PhabricatorRepositoryCommitChangeParserWorker::lookupOrCreatePaths(
+           ipull($syms, 'path'));
+
+  $symbol = new PhabricatorRepositorySymbol();
+  $conn_w = $symbol->establishConnection('w');
+
+  echo "Preparing queries...\n";
+  $sql = array();
+  foreach ($syms as $dict) {
+    $sql[] = qsprintf(
+                      $conn_w,
+                      '(%d, %s, %s, %s, %s, %d, %d)',
+                      $project->getID(),
+                      $dict['ctxt'],
+                      $dict['name'],
+                      $dict['type'],
+                      $dict['lang'],
+                      $dict['line'],
+                      $path_map[$dict['path']]);
+  }
+
+  if (!$no_purge) {
+    echo "Purging old syms...\n";
+    queryfx($conn_w,
+            'DELETE FROM %T WHERE arcanistProjectID = %d',
+            $symbol->getTableName(),
+            $project->getID());
+  }
+
+  echo "Loading ".number_format(count($sql))." syms...\n";
+  foreach (array_chunk($sql, 128) as $chunk) {
+    queryfx($conn_w,
+            'INSERT INTO %T
+      (arcanistProjectID, symbolContext, symbolName, symbolType,
+        symbolLanguage, lineNumber, pathID) VALUES %Q',
+            $symbol->getTableName(),
+            implode(', ', $chunk));
+  }
+
+}
+
+$no_purge = $args->getArg('no-purge');
 $symbols = array();
 foreach ($input as $key => $line) {
   try {
@@ -129,48 +183,26 @@ foreach ($input as $key => $line) {
       throw $e;
     }
   }
+
+  if (count ($symbols) >= $args->getArg('max-transaction')) {
+      try {
+        echo "Committing {$args->getArg('max-transaction')} symbols....\n";
+        commit_symbols($symbols, $project, $no_purge);
+        $no_purge = true;
+        unset($symbols);
+        $symbols = array();
+      } catch (Exception $e) {
+        if ($args->getArg('ignore-errors')) {
+          continue;
+        } else {
+          throw $e;
+        }
+      }
+  }
 }
 
-echo "Looking up path IDs...\n";
+if (count($symbols)) {
-$path_map = PhabricatorRepositoryCommitChangeParserWorker::lookupOrCreatePaths(
+  commit_symbols($symbols, $project, $args->getArg('no-purge'));
-  ipull($symbols, 'path'));
-
-$symbol = new PhabricatorRepositorySymbol();
-$conn_w = $symbol->establishConnection('w');
-
-echo "Preparing queries...\n";
-$sql = array();
-foreach ($symbols as $dict) {
-  $sql[] = qsprintf(
-    $conn_w,
-    '(%d, %s, %s, %s, %s, %d, %d)',
-    $project->getID(),
-    $dict['ctxt'],
-    $dict['name'],
-    $dict['type'],
-    $dict['lang'],
-    $dict['line'],
-    $path_map[$dict['path']]);
-}
-
-if (!$args->getArg('no-purge')) {
-  echo "Purging old symbols...\n";
-  queryfx(
-    $conn_w,
-    'DELETE FROM %T WHERE arcanistProjectID = %d',
-    $symbol->getTableName(),
-    $project->getID());
-}
-
-echo "Loading ".number_format(count($sql))." symbols...\n";
-foreach (array_chunk($sql, 128) as $chunk) {
-  queryfx(
-    $conn_w,
-    'INSERT INTO %T
-      (arcanistProjectID, symbolContext, symbolName, symbolType,
-        symbolLanguage, lineNumber, pathID) VALUES %Q',
-    $symbol->getTableName(),
-    implode(', ', $chunk));
 }
 
 echo "Done.\n";