GitHub user davies opened a pull request:
https://github.com/apache/spark/pull/15935
[SPARK-] add checksum for blocks of broadcast
## What changes were proposed in this pull request?
A TorrentBroadcast is serialized and compressed first, then splitted as
fixed size blocks, if any block is corrupt when fetching from remote, the
decompression/deserialization will fail without knowing which block is corrupt.
Also, the corrupt block is kept in block manager and reported to driver, so
other tasks (in same executor or from different executor) will also fail
because of it.
This PR add checksum for each block, and check it after fetching a block
from remote executor, because it's very likely that the corruption happen in
network. When the corruption happen, it will throw the block away and throw an
exception to fail the task, which will be retried.
## How was this patch tested?
Existing tests.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/davies/spark broadcast_checksum
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/spark/pull/15935.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #15935
----
commit 328ca390f10cceeb21656eb4fb9e0ef677fd0672
Author: Davies Liu <dav...@databricks.com>
Date: 2016-11-18T22:27:27Z
add checksum for blocks of broadcast
----
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
