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Author: squito

core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala

@@ -291,6 +291,9 @@ private[history] class FsHistoryProvider(conf: SparkConf, clock: Clock)
           try {
             val prevFileSize = fileToAppInfo.get(entry.getPath()).map{_.fileSize}.getOrElse(0L)
             !entry.isDirectory() &&
+              // FsHistoryProvider generates a hidden file which can't be read, and the user may
+              // generate others which can't be read.  Accidentally reading a garbage file is safe,
+              // but we would log an error which can be scary to the end-user.
               !entry.getPath().getName().startsWith(".") &&
               prevFileSize < entry.getLen()
           } catch {