NEO functional tests use pdb.wait() in a few places, for example in NEOCluster .run(), .start() and .expectCondition(). The wait implementation uses polling with exponentially growing wait period.

With the following instrumentation

--- a/neo/tests/cluster.py
+++ b/neo/tests/cluster.py
@@ -236,6 +236,7 @@ def wait(self, test, timeout):
                         return False
             finally:
                 cluster_dict.release()
+            print 'next_sleep:', next_sleep
             sleep(next_sleep)
         return True

during execution of functional tests it is not uncommon to see the following sleep periods

next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.15
next_sleep: 0.225
next_sleep: 0.3375
next_sleep: 0.50625
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.15
next_sleep: 0.225
next_sleep: 0.3375
next_sleep: 0.50625
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.15
next_sleep: 0.225
next_sleep: 0.3375
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.1
next_sleep: 0.15
next_sleep: 0.225
next_sleep: 0.3375
next_sleep: 0.50625

.

Without going into reworking the wait mechanism to use real notifications instead of polling, it was observed that the exponential progression tends to create too coarse sleeps. Initial 0.1s interval was found to be also too much.

This patch remove the exponential period growth and reduces period by order of one magnitude. For functional tests timings on my computer it is thus:

before patch:

Functional tests

28 Tests, 0 Failed

Title                     : TestRunner
Date                      : 2018-04-04
Node                      : deco
Machine                   : x86_64
System                    : Linux
Python                    : 2.7.14

Directory                 : /tmp/neo_tests/1522868674.115798
Status                    : 100.000%
NEO_TESTS_ADAPTER         : SQLite

                               NEO TESTS REPORT

              Test Module |  run  | unexpected | expected | skipped |  time
--------------------------+-------+------------+----------+---------+----------
                   Client |    6  |       .    |      .   |     .   |   8.51s
                  Cluster |    7  |       .    |      .   |     .   |   9.84s
                   Master |    4  |       .    |      .   |     .   |   9.68s
                  Storage |   11  |       .    |      .   |     .   |  20.76s
--------------------------+-------+------------+----------+---------+----------
     neo.tests.functional |       |            |          |         |
--------------------------+-------+------------+----------+---------+----------
                  Summary |   28  |       .    |      .   |     .   |  48.79s
--------------------------+-------+------------+----------+---------+----------

after patch:

Functional tests

28 Tests, 0 Failed

Title                     : TestRunner
Date                      : 2018-04-04
Node                      : deco
Machine                   : x86_64
System                    : Linux
Python                    : 2.7.14

Directory                 : /tmp/neo_tests/1522868527.624376
Status                    : 100.000%
NEO_TESTS_ADAPTER         : SQLite

                               NEO TESTS REPORT

              Test Module |  run  | unexpected | expected | skipped |  time
--------------------------+-------+------------+----------+---------+----------
                   Client |    6  |       .    |      .   |     .   |   7.38s
                  Cluster |    7  |       .    |      .   |     .   |   7.05s
                   Master |    4  |       .    |      .   |     .   |   8.22s
                  Storage |   11  |       .    |      .   |     .   |  19.22s
--------------------------+-------+------------+----------+---------+----------
     neo.tests.functional |       |            |          |         |
--------------------------+-------+------------+----------+---------+----------
                  Summary |   28  |       .    |      .   |     .   |  41.87s
--------------------------+-------+------------+----------+---------+----------

in other words ~ 10% improvement for the whole time to run functional tests.