hi,
we have some unit tests that run parallel that will create tmp keyspace,
and tables and then drop them after tests are done.

>From time to time, our create table statement run into "All hosts(s) for
query failed... Timeout during read" (from datastax driver) error.

We later turn on tracing, and record something  in the following.
See below between "===" , Native_Transport-Request thread and
MigrationStage thread, there was like 16 seconds doing something.

Any idea what that 16 seconds Cassandra was doing? We can work around that
but increasing our datastax driver timeout value, but wondering if there is
actually better way to solve this?

thanks



---------------- tracing ----------


5872bf70-e6e2-11e4-823d-93572f3db015 | 58730d97-e6e2-11e4-823d-93572f3db015
|
Key cache hit for sstable 95588 | 127.0.0.1 |           1592 |
Native-Transport-Requests:102
5872bf70-e6e2-11e4-823d-93572f3db015 | 58730d98-e6e2-11e4-823d-93572f3db015
|                                                                   Seeking
to partition beginning in data file | 127.0.0.1 |           1593 |
Native-Transport-Requests:102
5872bf70-e6e2-11e4-823d-93572f3db015 | 58730d99-e6e2-11e4-823d-93572f3db015
|
Merging data from memtables and 3 sstables | 127.0.0.1 |           1595 |
Native-Transport-Requests:102

=====================
5872bf70-e6e2-11e4-823d-93572f3db015 | 58730d9a-e6e2-11e4-823d-93572f3db015
|
Read 3 live and 0 tombstoned cells | 127.0.0.1 |           1610 |
Native-Transport-Requests:102
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a40-e6e2-11e4-823d-93572f3db015
|               Executing seq scan across 1 sstables for
(min(-9223372036854775808), min(-9223372036854775808)] | 127.0.0.1 |
16381594 |              MigrationStage:1
=====================

5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a41-e6e2-11e4-823d-93572f3db015
|                                                                   Seeking
to partition beginning in data file | 127.0.0.1 |       16381782
|              MigrationStage:1
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a42-e6e2-11e4-823d-93572f3db015
|
Read 0 live and 0 tombstoned cells | 127.0.0.1 |       16381787
|              MigrationStage:1
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a43-e6e2-11e4-823d-93572f3db015
|                                                                   Seeking
to partition beginning in data file | 127.0.0.1 |       16381789
|              MigrationStage:1
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a44-e6e2-11e4-823d-93572f3db015
|
Read 0 live and 0 tombstoned cells | 127.0.0.1 |       16381791
|              MigrationStage:1
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a45-e6e2-11e4-823d-93572f3db015
|                                                                   Seeking
to partition beginning in data file | 127.0.0.1 |       16381792
|              MigrationStage:1
5872bf70-e6e2-11e4-823d-93572f3db015 | 62364a46-e6e2-11e4-823d-93572f3db015
|
Read 0 live and 0 tombstoned cells | 127.0.0.1 |       16381794
|              MigrationStage:1
.
.
.

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