choreography vs orchestration

I see in more and more articles that authors are using both terms interchangeably. As far as I can tell there is no formal definition, just like with terms agile, microservices, SOA, but... in ancient days when I was studding computer science on a university there was a difference:

• choreography: distributed decision making
• orchestration: centralised decision making

JavaScript Exceptions vs. Errors

A JavaScript exception is a value that is thrown as a result of an invalid operation or as the target of a throw statement. While it is not required that these values are instances of Error or classes which inherit from Error, all exceptions thrown by Node.js or the JavaScript runtime will be instances of Error.

Some exceptions are unrecoverable at the JavaScript layer. Such exceptions will always cause the Node.js process to crash.

This is why you can write:
throw new Exception("foo bar");
throw "foo bar";

TPC-C current benchmarks for stateful and stateless services running Java.

• Immediately consistency: 1 box: 2000 requests/second with 5 second response time
• Eventually consistent: 1 box: 300 requests/second with a 100 millisecond response time.

It is all achivable, if you are not there you need tools to figure out why.
Switch to stateless services whenever possible. A great article about pushing the boundaries and how important it is in HFT is available in barbarians at the gateways.

No versions found in startbootstrap-sb-admin-2.git

No versions found in https://github.com/IronSummitMedia/startbootstrap-sb-admin-2.git

The problem manifests itself because IronSummitMedia changed it's name to BlackrockDigital and you should go and install a different package from:

https://github.com/BlackrockDigital/startbootstrap-sb-admin-2

Waking up Heroku app

Deployment is not enough to wake it up. I just hit the URL in the browser :) Unfortunately if you use a free dyno for a hugbot that is integrated with slack, you need to wake your dyno up after recharging period.

young-sands-45836.herokuapp.com

Oracle PLSQL alert table add not null column with default value throws exception

I was trying to run following script:

alter table qrtz_blob_triggers add sched_name varchar(120) not null DEFAULT 'TestScheduler';

I kept receiving a following exception:

alter table qrtz_blob_triggers add sched_name varchar(120) not null DEFAULT 'TestScheduler'
Error report -
SQL Error: ORA-30649: missing DIRECTORY keyword
30649.0000 -  "missing DIRECTORY keyword"
*Cause:    DEFAULT DIRECTORY clause missing or incorrect.
*Action:   Provide the DEFAULT DIRECTORY.

I had to change the order of a query (default before not null):

alter table qrtz_blob_triggers add sched_name varchar(120) DEFAULT 'TestScheduler' not null;

I will keep this as an example for people that keep telling me that SQL is a declarative/functional language, and not something that Scarily Qualifies as a Language

Maven command to run tests in a selected module and ignore failures and redirect output to a file

This is useful when I want to see all the failed tests, and I want to have it in file so I can easily navigate thru entire output - for example to search for errors.

mvn -f system-tests/pom.xml -Dmaven.test.failure.ignore=true clean install > myout.txt