Presentation: PID Loops and the Art of Keeping Systems Stable

Track: Modern CS in the Real World

Location: Broadway Ballroom South Center, 6th fl.

Duration: 11:50am - 12:40pm

Day of week: Monday

Share this on:


Building ultra-reliable large-scale services is an incredible challenge. Systems often exhibit emergent properties and network effects that can be beyond the practical limits of testing, how do we keep things stable even when the unpredictable happens? Control theory, a branch of engineering that has existed for over a hundred years has a lot to offer us. Systems of all sizes can be analyzed and stabilized with PID control loops - often simple algorithms that contain Propotional, Integral, and Derivative components. But how? This session will show what PID loops look like in the context of modern systems, and to see how expoential backoff, flow-control, and other techniques can be wielded to build self-healing systems.

Speaker: Colm MacCárthaigh

Senior Principal Engineer @awscloud

Colm is an engineer at Amazon Web Services. For just over ten years Colm has been building some of the largest services at AWS, including Amazon EC2, S3, ELB, CloudFront, and Route53.  Colm is also an active Open Source contributor and is the main author of Amazon s2n, AWS's Open Source implementation of TLS/SSL, as well as a member of the Apache Software Foundation and a core contributor to Apache httpd and apr. In evenings and weekends, Colm is an Irish folk musician and singer and regular tours, produces and records albums, and enjoys teaching workshops. 

Find Colm MacCárthaigh at


Monday, 24 June

Tuesday, 25 June

Wednesday, 26 June