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https://issues.apache.org/jira/browse/FLINK-6798?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16038780#comment-16038780
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ASF GitHub Bot commented on FLINK-6798:
---------------------------------------

Github user zentol commented on a diff in the pull request:

    https://github.com/apache/flink/pull/4080#discussion_r120343058
  
    --- Diff: docs/monitoring/large_state_tuning.md ---
    @@ -94,21 +94,11 @@ When a savepoint is manually triggered, it may be in 
process concurrently with a
     
     ## Tuning Network Buffers
     
    -The number of network buffers is a parameter that can currently have an 
effect on checkpointing at large scale.
    -The Flink community is working on eliminating that parameter in the next 
versions of Flink.
    -
    -The number of network buffers defines how much data a TaskManager can hold 
in-flight before back-pressure kicks in.
    -A very high number of network buffers means that a lot of data may be in 
the stream network channels when a checkpoint
    -is started. Because the checkpoint barriers travel with that data (see 
[description of how checkpointing 
works](../internals/stream_checkpointing.html)),
    -a lot of in-flight data means that the barriers have to wait for that data 
to be transported/processed before arriving
    -at the target operator.
    -
    -Having a lot of data in-flight also does not speed up the data processing 
as a whole. It only means that data is picked up faster
    -from the data source (log, files, message queue) and buffered longer in 
Flink. Having fewer network buffers means that
    -data is picked up from the source more immediately before it is actually 
being processed, which is generally desirable.
    -The number of network buffers should hence not be set arbitrarily large, 
but to a low multiple (such as 2x) of the
    -minimum number of required buffers.
    -
    +Previously, an increased number of network buffers also caused increased 
checkpointing times since
    --- End diff --
    
    Replace "Previously" with an absolute reference, i.e "Before 1.3".


> Remove/update documentation about network buffer tuning
> -------------------------------------------------------
>
>                 Key: FLINK-6798
>                 URL: https://issues.apache.org/jira/browse/FLINK-6798
>             Project: Flink
>          Issue Type: Sub-task
>          Components: Documentation, Network
>            Reporter: Robert Metzger
>            Assignee: Nico Kruber
>             Fix For: 1.3.0
>
>
> {quote}The number of network buffers is a parameter that can currently have 
> an effect on checkpointing at large scale. The Flink community is working on 
> eliminating that parameter in the next versions of Flink.
> {quote} 
> in 
> https://ci.apache.org/projects/flink/flink-docs-release-1.3/monitoring/large_state_tuning.html#tuning-network-buffers



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