Package org.apache.flink.runtime.io.network.buffer

Class BufferConsumerWithPartialRecordLength

java.lang.Object
org.apache.flink.runtime.io.network.buffer.BufferConsumerWithPartialRecordLength
@NotThreadSafe public class BufferConsumerWithPartialRecordLength extends Object
BufferConsumer with partial record length if a record is spanning over buffers

`partialRecordLength` is the length of bytes to skip in order to start with a complete record, from position index 0 of the underlying MemorySegment. `partialRecordLength` is used in approximate local recovery to find the start position of a complete record on a BufferConsumer, so called `partial record clean-up`.

Partial records happen if a record can not fit into one buffer, then the remaining part of the same record is put into the next buffer. Hence partial records only exist at the beginning of a buffer. Partial record clean-up is needed in the mode of approximate local recovery. If a record is spanning over multiple buffers, and the first (several) buffers have got lost due to the failure of the receiver task, the remaining data belonging to the same record in transition should be cleaned up.

If partialRecordLength == 0, the buffer starts with a complete record

If partialRecordLength > 0, the buffer starts with a partial record, its length = partialRecordLength

If partialRecordLength < 0, partialRecordLength is undefined. It is currently used in

  • Constructor Details

    • BufferConsumerWithPartialRecordLength

      public BufferConsumerWithPartialRecordLength(BufferConsumer bufferConsumer, int partialRecordLength)

  • Method Details

    • getBufferConsumer

      public BufferConsumer getBufferConsumer()

    • getPartialRecordLength

      public int getPartialRecordLength()

    • build

      public Buffer build()

    • cleanupPartialRecord

      public boolean cleanupPartialRecord()