Impala Public Jenkins has submitted this change and it was merged.

Change subject: IMPALA-3794: Workaround for Breakpad ID conflicts
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IMPALA-3794: Workaround for Breakpad ID conflicts

Breakpad determines the ID of the minidump file to be written in case of
a crash during startup of the process randomly, seeded with the current
system time with second granularity. If two impalads start up within the
same second, there is a chance for a name conflict. The one second delay
between starting impalads in start-impala-cluster.py is not sufficient:

I0407 22:34:52.018563 28473 minidump.cc:245] Setting minidump size limit
to 20971520.
I0407 22:34:52.997046 28749 minidump.cc:245] Setting minidump size limit
to 20971520.

When sending a signal to all of them, one process can overwrite the
minidump of another one. This is an upstream issue and is tracked in
Breakpad-681. I further confirmed my suspicion by tentatively making an
own output folder for each running instance of impalad and was then
unable to reproduce the issue. However, it is a more clear solution to
fix the underlying issue than to change the folder locations for
minidumps in impala.

Until this is fixed upstream, we can make sure that we see at least one
minidump for the group of impalads in the test cluster. It is not a
product defect, since we don't support running multiple impalads on a
single host, let alone starting them all at once.

To test this I ran the following loop for about an hour on my dev
machine without hitting the issue:

while [ $? -eq 0 ]; do impala-py.test
tests/custom_cluster/test_breakpad.py --exploration_strategy=exhaustive
-k test_minidump_relative_path -x -s; done

Change-Id: I4ae589f6eb5cbbfb860943214edc0e6415eeb862
Reviewed-on: http://gerrit.cloudera.org:8080/6588
Reviewed-by: Lars Volker <[email protected]>
Tested-by: Impala Public Jenkins
---
M tests/custom_cluster/test_breakpad.py
1 file changed, 22 insertions(+), 15 deletions(-)

Approvals:
  Impala Public Jenkins: Verified
  Lars Volker: Looks good to me, approved



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Gerrit-MessageType: merged
Gerrit-Change-Id: I4ae589f6eb5cbbfb860943214edc0e6415eeb862
Gerrit-PatchSet: 8
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Lars Volker <[email protected]>
Gerrit-Reviewer: Bharath Vissapragada <[email protected]>
Gerrit-Reviewer: Impala Public Jenkins
Gerrit-Reviewer: Lars Volker <[email protected]>
Gerrit-Reviewer: Michael Brown <[email protected]>

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