Flaky Tests

[shuhaowu]

In ghostferry.tests.TestIgnoresTables:

--- FAIL: TestIgnoresTables (1.70s)
	Error Trace:	iterative_verifier_integration_test.go:139
			integration_test_case.go:158
			integration_test_case.go:105
			integration_test_case.go:42
			integration_test_case.go:33
			iterative_verifier_integration_test.go:153
	Error:		Should be true

Some deadlocking issues:

ERRO[0006] failed to write events to target, 1 of 5 max retries  error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=binlog_writer
ERRO[0006] failed to write events to target, 2 of 5 max retries  error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=binlog_writer
ERRO[0006] failed to write events to target, 3 of 5 max retries  error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=binlog_writer
ERRO[0006] failed to write events to target, 4 of 5 max retries  error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=binlog_writer
ERRO[0006] failed to write events to target after 5 attempts, retry limit exceeded  error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=binlog_writer
ERRO[0006] fatal error detected, state dump coming in stdout  errfrom=binlog_writer error="exec query (445 bytes): Error 1213: Deadlock found when trying to get lock; try restarting transaction" tag=error_handler
{
  "CompletedTables": {},
  "LastSuccessfulBinlogPos": {
    "Name": "mysql-bin.000003",
    "Pos": 852531
  },
  "LastSuccessfulPrimaryKeys": {
    "gftest.table1": 459
  }
}
panic: fatal error detected, see logs for details

goroutine 1624 [running]:
github.com/Shopify/ghostferry.(*PanicErrorHandler).Fatal(0xc422171090, 0x8d27a3, 0xd, 0xb502a0, 0xc422fa6140)
	/home/ubuntu/.go_project/src/github.com/Shopify/ghostferry/error_handler.go:44 +0x70a
github.com/Shopify/ghostferry.(*BinlogWriter).Run(0xc420220af0)
	/home/ubuntu/.go_project/src/github.com/Shopify/ghostferry/binlog_writer.go:60 +0x37d
github.com/Shopify/ghostferry.(*Ferry).Run.func4(0xc422e91ba0, 0xc420492b40)
	/home/ubuntu/.go_project/src/github.com/Shopify/ghostferry/ferry.go:288 +0x55
created by github.com/Shopify/ghostferry.(*Ferry).Run
	/home/ubuntu/.go_project/src/github.com/Shopify/ghostferry/ferry.go:286 +0x249
exit status 2
FAIL	github.com/Shopify/ghostferry/test	6.349s

[shuhaowu]

Duplicate of #107