Why does my ruby crash / segfault during tests?

Question

I've read in places that it might have something to do with sqlite3, but my googling has yielded nothing helpful. Here is an example of the error: https://travis-ci.org/NullVoxPopuli/aeonvera/jobs/61047991

It seems to happen randomly - both on my machine, and on travis. So I end up having to re-run rspec until it passes - which is pretty annoying, as my test suite takes a couple minutes to run.

How is this caused? and how do I prevent it? It's kind of silly to have to be actively engaged with your CI to re-run specs until it passes.

I'm using sqlite3 to run all my specs in memory - which is a nice speed bonus, and also helps me make sure I'm not doing any db-specific queries (my production app uses pgsql)

Here is a link to my repo if anyone is curious: https://github.com/NullVoxPopuli/aeonvera

UPDATE

This isn't sqlite3 specific - it happens when using postgresql as well.

stacktrace

/home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/postgresql/database_statements.rb:128: [BUG] Segmentation fault at 0x000000000001d4
ruby 2.2.1p85 (2015-02-26 revision 49769) [x86_64-linux]

-- Control frame information -----------------------------------------------
c:0057 p:---- s:0311 e:000310 CFUNC  :backtrace
c:0056 p:0009 s:0310 e:000309 RESCUE /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/notifications/instrumenter.rb:25
c:0055 p:0037 s:0307 e:000305 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/notifications/instrumenter.rb:25
c:0054 p:0034 s:0300 e:000299 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract_adapter.rb:378
c:0053 p:0014 s:0292 e:000291 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/postgresql/database_statement
c:0052 p:0019 s:0286 e:000286 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/savepoints.rb:17
c:0051 p:0014 s:0283 e:000282 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/transaction.rb:114
c:0050 p:0009 s:0280 e:000279 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/database_statements.
c:0049 p:0018 s:0277 e:000276 RESCUE /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/database_statements.
c:0048 p:0035 s:0274 e:000272 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/database_statements.
c:0047 p:0078 s:0267 e:000266 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/connection_adapters/abstract/database_statements.
c:0046 p:0017 s:0263 e:000262 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/transactions.rb:208
c:0045 p:0014 s:0262 E:001878 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activerecord-4.1.10/lib/active_record/transactions.rb:326
c:0044 p:0010 s:0256 e:000255 RESCUE
c:0043 p:---- s:0225 e:000221 CFUNC  :initialize_copy
c:0042 p:---- s:0221 e:000220 CFUNC  :unlock
c:0041 p:0024 s:0223 e:000220 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/backtrace_cleaner.rb:10 [FINISH]
c:0040 p:---- s:0218 e:000217 CFUNC  :call
c:0039 p:0012 s:0214 e:000213 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/backtrace_cleaner.rb:85 [FINISH]
c:0038 p:---- s:0211 e:000210 CFUNC  :map
c:0037 p:0010 s:0208 e:000207 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/backtrace_cleaner.rb:85 [FINISH]
c:0036 p:---- s:0205 e:000204 CFUNC  :each
c:0035 p:0011 s:0202 e:000201 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/backtrace_cleaner.rb:84
c:0034 p:0015 s:0198 e:000197 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/backtrace_cleaner.rb:37
c:0033 p:0025 s:0192 e:000191 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/exception_wrapper.rb:89
c:0032 p:0009 s:0188 e:000187 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/exception_wrapper.rb:49
c:0031 p:0037 s:0185 e:000184 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/debug_exceptions.rb:74
c:0030 p:0028 s:0177 e:000176 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/debug_exceptions.rb:34
c:0029 p:0045 s:0166 e:000165 RESCUE /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/debug_exceptions.rb:27
c:0028 p:0091 s:0163 e:000162 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/debug_exceptions.rb:17
c:0027 p:0011 s:0154 e:000153 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/show_exceptions.rb:30
c:0026 p:0077 s:0149 e:000148 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/rack/logger.rb:38
c:0025 p:0011 s:0142 e:000141 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/rack/logger.rb:20
c:0024 p:0007 s:0140 e:000139 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/tagged_logging.rb:68
c:0023 p:0018 s:0138 e:000137 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/tagged_logging.rb:26
c:0022 p:0013 s:0133 e:000132 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/tagged_logging.rb:68
c:0021 p:0042 s:0129 e:000128 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/rack/logger.rb:20
c:0020 p:0077 s:0124 e:000123 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/quiet_assets-1.1.0/lib/quiet_assets.rb:27
c:0019 p:0011 s:0120 e:000119 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/request_store-1.1.0/lib/request_store/middleware.rb:8
c:0018 p:0031 s:0116 e:000115 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/request_id.rb:21
c:0017 p:0071 s:0112 e:000111 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/methodoverride.rb:21
c:0016 p:0024 s:0107 e:000106 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/runtime.rb:17
c:0015 p:0035 s:0098 e:000097 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/activesupport-4.1.10/lib/active_support/cache/strategy/local_cache_middleware.rb:26
c:0014 p:0091 s:0093 e:000092 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/actionpack-4.1.10/lib/action_dispatch/middleware/static.rb:84
c:0013 p:0011 s:0087 e:000086 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/sendfile.rb:112
c:0012 p:0058 s:0077 e:000076 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/engine.rb:514
c:0011 p:0036 s:0073 e:000072 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/railties-4.1.10/lib/rails/application.rb:144
c:0010 p:0011 s:0069 e:000068 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/builder.rb:138
c:0009 p:0148 s:0065 e:000064 BLOCK  /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/urlmap.rb:65 [FINISH]
c:0008 p:---- s:0057 e:000056 CFUNC  :each
c:0007 p:0054 s:0054 e:000053 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/urlmap.rb:50
c:0006 p:0045 s:0045 e:000044 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/capybara-2.4.4/lib/capybara/server.rb:19
c:0005 p:0301 s:0040 e:000039 METHOD /home/preston/.rvm/gems/ruby-2.2.1/gems/rack-1.5.3/lib/rack/handler/webrick.rb:60
c:0004 p:0211 s:0028 e:000027 METHOD /home/preston/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/webrick/httpserver.rb:138
c:0003 p:0370 s:0018 e:000017 METHOD /home/preston/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/webrick/httpserver.rb:94
c:0002 p:0103 s:0007 e:000006 BLOCK  /home/preston/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/webrick/server.rb:294 [FINISH]
c:0001 p:---- s:0002 e:000001 TOP    [FINISH]

All the other information: http://pastebin.com/d6Tm13ww

Answer 1

You can try to step back in your git history until you have a state where it is stable. And from there introduce changes to isolate the 'bad' change.

Also, you should avoid using on sqlite3 even in tests. Tests should be as close to production as possible.