@Entity
data class Thing (
    @Id
    var id: Long,
    var value: String
)

# download
wget -qO- https://binaries.cockroachdb.com/cockroach-v1.1.5.linux-amd64.tgz | tar xvz

# start
./cockroach-v1.1.5.linux-amd64/cockroach start --insecure
# leave terminal open in background

# init
cockroach sql --insecure -e "CREATE USER root WITH PASSWORD '123';"
cockroach sql --insecure -e "CREATE DATABASE things_db;"
cockroach sql --insecure -e "GRANT ALL ON DATABASE things_db TO root;"

gradle bootRun
# leave terminal open in background

python3 stress_test.py

PUT OK
find OK
PUT OK
find OK
find OK
find OK
PUT ERROR: {"timestamp":"2018-03-17T16:00:24.616+0000","status":500,"error":"Internal Server Error","message":"Unable to commit against JDBC Connection; nested exception is org.hibernate.TransactionException: Unable to commit against JDBC Connection","path":"/thing/"}
find OK
PUT OK

2018-03-17 17:00:24.615 ERROR 3547 --- [nio-8082-exec-6] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.orm.jpa.JpaSystemException: Unable to commit against JDBC Connection; nested exception is org.hibernate.TransactionException: Unable to commit against JDBC Connection] with root cause

org.postgresql.util.PSQLException: ERROR: restart transaction: HandledRetryableTxnError: TransactionRetryError: retry txn (RETRY_SERIALIZABLE): "sql txn" id=1cb57665 key=/Table/51/1/11125601/0 rw=true pri=0.04354217 iso=SERIALIZABLE stat=PENDING epo=0 ts=1521302424.604752770,1 orig=1521302424.604725980,0 max=1521302424.604725980,0 wto=false rop=false seq=3