[kudu-CR] [client-test] added basic test for RWYW behavior

["Alexey Serbin (Code Review)" <ge...@cloudera.org>]

Alexey Serbin has posted comments on this change.

Change subject: [client-test] added basic test for RWYW behavior
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Patch Set 1:

> I have an ambivalent opinion regarding this test.
 > 
 > Read Your Writes means that a client can _always_ observe the write
 > that was performed. If that is not the case then it's not RYW. We
 > currently have gaps in our consistency story that we're looking to
 > solve, so we don't get RYW in rare cases. To get around this the
 > test loops until RYW occurs, which goes against the nature of what
 > its testing. After all even the least consistent of eventual
 > consistent databases would likely pass a test like this, given
 > enough retries.

The test loops when it sees timeout from a tablet replica catching-up, not just to get expected number or rows.

 > 
 > This is not to say that this test is without merit, IMO we could go
 > about it two different ways:
 > 
 > - Add this without the loops as a DISABLED_ test
 > - Keep this patch open and re-evaluate merging later.
 > 
 > That being said while fixing our consistency story we'll have to
 > come with much more adversarial tests (with node kills, stops,
 > elections, etc).

Yes, this is a very basic test to explicitly exercise 'timestamp + 1' notion.  It does not pretend to be an exhaustive one -- that one should be among integration tests, not here.

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Gerrit-MessageType: comment
Gerrit-Change-Id: I3c237a41a1434199848ac5fc978fab27e565e2d8
Gerrit-PatchSet: 1
Gerrit-Project: kudu
Gerrit-Branch: master
Gerrit-Owner: Alexey Serbin <as...@cloudera.com>
Gerrit-Reviewer: Adar Dembo <ad...@cloudera.com>
Gerrit-Reviewer: Alexey Serbin <as...@cloudera.com>
Gerrit-Reviewer: David Ribeiro Alves <dr...@apache.org>
Gerrit-Reviewer: Kudu Jenkins
Gerrit-Reviewer: Tidy Bot
Gerrit-HasComments: No