Avoiding insurmountable queue backlogs

Queues offer a promise of reliability for integrating applications, but can cause more subtle operational risks.

Queues exhibit ‘bi-modal behavior’ — low latency when everything is working well, but can rapidly form large backlogs when a failure occurs. This can dramatically increase the recovery time from outages.

Amazon offer an extremely interesting article about the reliability of queuing, with strategies to limit and manage backlogging.

Bad auto-completions in Eclipse

Eclipse recently has suffered increasing numbers of questionable autocompletions — sometimes auto-wrongly replacing  perfectly good code typed by the developer.

While there might be a few underlying issues, I found replacing “map.put()” with “map.compute()” particularly annoying and went to investigate. Here’s the solution.

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HTTP Status Reason broken in Tomcat 9

Just today, I found the “amusing” fact that Tomcat server developers have taken it upon themselves to delete support for the HTTP Status Reason.

Think “200 OK” or “404 Not Found”. Even for applications sending a reason & clients expecting it, Tomcat is coded to explicitly drop the value — sending just a bald 200 or 404.

Unsurprisingly for those with the slightest knowledge of protocol compatibility, this is now breaking clients in the wild.

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