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From uce <...@git.apache.org>
Subject [GitHub] incubator-flink pull request: [FLINK-1323] Add an I/O writer imple...
Date Tue, 11 Nov 2014 10:39:52 GMT
Github user uce commented on a diff in the pull request:

    --- Diff: flink-runtime/src/main/java/org/apache/flink/runtime/io/disk/iomanager/BlockChannelWriter.java
    @@ -16,101 +16,40 @@
      * limitations under the License.
     package org.apache.flink.runtime.io.disk.iomanager;
     import java.io.IOException;
     import java.util.concurrent.LinkedBlockingQueue;
    -import java.util.concurrent.TimeUnit;
     import org.apache.flink.core.memory.MemorySegment;
      * A writer that writes data in blocks to a file channel. The writer receives the data
blocks in the form of 
      * {@link org.apache.flink.core.memory.MemorySegment}, which it writes entirely to the
    - * regardless of how space in the segment is used. The writing happens in an asynchronous
fashion. That is, a write
    - * request is not processed by the thread that issues it, but by an asynchronous writer
thread. Once the request
    - * is done, the asynchronous writer adds the MemorySegment to a <i>return queue</i>
where it can be popped by the
    - * worker thread, to be reused. The return queue is in this case a
    - * {@link java.util.concurrent.LinkedBlockingQueue}, such that the working thread blocks
until the request has been served,
    - * if the request is still pending when the it requires the segment back. 
    - * <p>
    - * Typical write behind is realized, by having a small set of segments in the return
queue at all times. When a
    - * memory segment must be written, the request is issued to the writer and a new segment
is immediately popped from
    - * the return queue. Once too many requests have been issued and the I/O thread cannot
keep up, the working thread
    - * naturally blocks until another segment is available again.
    + * regardless of how space in the segment is used. The writing may be realized synchronously,
or asynchronously,
    + * depending on the implementation. To support 
    --- End diff --
    trivial: comment ends apruptly

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