apache/hadoop · error · IOException

Only read ${actualNumDirectives} cache pools out of ${expect

Error message

Only read ${actualNumDirectives} cache pools out of ${expectedNumDirectives}

What it means

Error "Only read ${actualNumDirectives} cache pools out of ${expectedNumDirectives}" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineImageViewer/OfflineImageReconstructor.java:1113

      long actualNumPools = 0;
      while (actualNumPools < expectedNumPools) {
        try {
          expectTag(CACHE_MANAGER_SECTION_POOL, false);
        } catch (IOException e) {
          throw new IOException("Only read " + actualNumPools +
              " cache pools out of " + expectedNumPools, e);
        }
        actualNumPools++;
        Node pool = new Node();
        loadNodeChildren(pool, "pool fields", "");
        processPoolXml(node);
      }
      long actualNumDirectives = 0;
      while (actualNumDirectives < expectedNumDirectives) {
        try {
          expectTag(CACHE_MANAGER_SECTION_DIRECTIVE, false);
        } catch (IOException e) {
          throw new IOException("Only read " + actualNumDirectives +
              " cache pools out of " + expectedNumDirectives, e);
        }
        actualNumDirectives++;
        Node pool = new Node();
        loadNodeChildren(pool, "directive fields", "");
        processDirectiveXml(node);
      }
      expectTagEnd(CACHE_MANAGER_SECTION_NAME);
      recordSectionLength(SectionName.CACHE_MANAGER.name());
    }

    private void processPoolXml(Node pool) throws IOException {
      CachePoolInfoProto.Builder bld = CachePoolInfoProto.newBuilder();
      String poolName =
          pool.removeChildStr(CACHE_MANAGER_SECTION_POOL_NAME);
      if (poolName == null) {
        throw new IOException("<pool> found without <poolName>");
      }

View on GitHub (pinned to 2add963021)

Solutions

1. The XML is truncated or its <numDirectives> count is wrong; correct the count or add the missing <directive> stanzas.
2. Regenerate the fsimage XML with 'hdfs oiv' from a valid fsimage.

When it happens

Trigger: Thrown by oiv -r when fewer cache directive stanzas are present than the count declared by <numDirectives>.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/d1ad0c833b31b788. Report an issue: GitHub.