Question

这是我的solrconfig.xml文件的默认设置：

 <autoSoftCommit> 
   <maxTime>${solr.autoSoftCommit.maxTime:-1}</maxTime> 
 </autoSoftCommit>

maxTime为'-1'是否表示自动软提交已关闭？如果是这样，如果我完全删除了标签，我会得到相同的结果吗？如果我必须手动执行软提交，可以使用'commitWithin'（我用Google搜索但是得到了相互矛盾的答案）吗？

哦，我正在使用Solr 4.5.0

Answer 1

首先，您可以在标记中看到表达式${solr.autoSoftCommit.maxTime:-1}。这允许您使用Solr的变量替换。该功能详细描述here in the reference。如果该变量未被任何方式替换，则-1被视为该配置的值。

将commitMaxTime转为-1 有效地关闭了自动提交。如果你看一下下面的相关代码，你可以看到commitMaxTime否决了maxDocs的任何值，因为scheduleCommitWithin方法立即返回。我没有发现记录这种行为，所以我查了一下代码。

private void _scheduleCommitWithin(long commitMaxTime) {
    if (commitMaxTime <= 0) return;
    synchronized (this) {
      if (pending != null && pending.getDelay(TimeUnit.MILLISECONDS) <= commitMaxTime) {
        // There is already a pending commit that will happen first, so
        // nothing else to do here.
        // log.info("###returning since getDelay()==" + pending.getDelay(TimeUnit.MILLISECONDS) + " less than " + commitMaxTime);

        return;
      }

      if (pending != null) {
        // we need to schedule a commit to happen sooner than the existing one,
        // so lets try to cancel the existing one first.
        boolean canceled = pending.cancel(false);
        if (!canceled) {
          // It looks like we can't cancel... it must have just started running!
          // this is possible due to thread scheduling delays and a low commitMaxTime.
          // Nothing else to do since we obviously can't schedule our commit *before*
          // the one that just started running (or has just completed).
          // log.info("###returning since cancel failed");
          return;
        }
      }

      // log.info("###scheduling for " + commitMaxTime);

      // schedule our new commit
      pending = scheduler.schedule(this, commitMaxTime, TimeUnit.MILLISECONDS);
    }
}

取自https://github.com/apache/lucene-solr/blob/lucene_solr_4_5/solr/core/src/java/org/apache/solr/update/CommitTracker.java

对于问题的第二部分，如果一起删除标记，则与将值设置为-1的结果相同。如下所示，如果xpath表达式返回null，则将获得-1作为默认值。

但是从配置中删除整个表达式也将删除通过Solr的变量替换覆盖该配置的选项。

protected UpdateHandlerInfo loadUpdatehandlerInfo() { return new UpdateHandlerInfo(get("updateHandler/@class",null), getInt("updateHandler/autoCommit/maxDocs",-1), getInt("updateHandler/autoCommit/maxTime",-1), getBool("updateHandler/autoCommit/openSearcher",true), getInt("updateHandler/commitIntervalLowerBound",-1), getInt("updateHandler/autoSoftCommit/maxDocs",-1), getInt("updateHandler/autoSoftCommit/maxTime",-1), getBool("updateHandler/commitWithin/softCommit",true)); }

取自https://github.com/apache/lucene-solr/blob/lucene_solr_4_5/solr/core/src/java/org/apache/solr/core/SolrConfig.java

SOLR：autoSoftCommit最大时间-1是什么意思？

1 个答案: