If you’ve been submitting jobs on Sherlock over the last couple days, you probably noticed something different about your your job ids… They lost a couple digits!

If you submitted a job last week, its job id was likely in the 67,000,000s. Today, it’s back in the 100,000s. What happened? Did we reset anything? Did we start simplifying job ids because there were too many numbers to keep track of?

Not really.

It’s just that so many jobs are submitted to Sherlock these days (and even more so since the beginning of the stay-at-home directives), that we reached the maximum job id that the scheduler can use.

Those job ids are roughly 26 bits in length, with a little headroom for special cases, and the largest job id that the scheduler can assign on Sherlock is 67,043,327. It means that when that number is reached, the next submitted job will be assigned jobid #1.

Both were submitted on Friday night, and started running Saturday morning:

       JobID  Partition              Submit               Start
------------ ---------- ------------------- -------------------
1                normal 2020-05-08T22:21:28 2020-05-09T06:04:50
67043327         normal 2020-05-08T22:21:28 2020-05-09T06:05:16

A few months ago, we celebrated job #50,000,000. Today, we’re celebrating job #1, the beginning of a new cycle. :)

Thanks to each and every one of you, Sherlock users, for your continuous support, your extraordinary motivation and all of your patience and understanding when things break. We’ve never been so proud of supporting your amazing work, especially during those particularly trying times. Stay safe and happy computing!