spark-instrumented-optimizer/core
“attilapiros” cdc8fc6233 [SPARK-30235][CORE] Switching off host local disk reading of shuffle blocks in case of useOldFetchProtocol
### What changes were proposed in this pull request?

When `spark.shuffle.useOldFetchProtocol` is enabled then switching off the direct disk reading of host-local shuffle blocks and falling back to remote block fetching (and this way avoiding the `GetLocalDirsForExecutors` block transfer message which is introduced from Spark 3.0.0).

### Why are the changes needed?

In `[SPARK-27651][Core] Avoid the network when shuffle blocks are fetched from the same host` a new block transfer message is introduced, `GetLocalDirsForExecutors`. This new message could be sent to the external shuffle service and as it is not supported by the previous version of external shuffle service it should be avoided when `spark.shuffle.useOldFetchProtocol` is true.

In the migration guide I changed the exception type as `org.apache.spark.network.shuffle.protocol.BlockTransferMessage.Decoder#fromByteBuffer`
throws a IllegalArgumentException with the given text and uses the message type which is just a simple number (byte). I have checked and this is true for version 2.4.4 too.

### Does this PR introduce any user-facing change?
No.

### How was this patch tested?

This specific case (considering one extra boolean to switch off host local disk reading feature) is not tested but existing tests were run.

Closes #26869 from attilapiros/SPARK-30235.

Authored-by: “attilapiros” <piros.attila.zsolt@gmail.com>
Signed-off-by: Marcelo Vanzin <vanzin@cloudera.com>
2019-12-17 10:32:15 -08:00
..
benchmarks [SPARK-29576][CORE] Use Spark's CompressionCodec for Ser/Deser of MapOutputStatus 2019-10-23 18:17:37 -07:00
src [SPARK-30235][CORE] Switching off host local disk reading of shuffle blocks in case of useOldFetchProtocol 2019-12-17 10:32:15 -08:00
pom.xml [INFRA] Reverts commit 56dcd79 and c216ef1 2019-12-16 19:57:44 -07:00