Re: Q2 2024 Transparency Report on Boost C++ Library

From: Boris Kolpackov (boris_at_[hidden])
Date: 2024-07-20 15:58:10

Sam Darwin <samuel.d.darwin_at_[hidden]> writes:

> The CI jobs we're hosting burst up to 500 simultaneous jobs. Is it
> enough? The solution is autoscaling (on AWS).

In my experience, the cost (in engineering complexity and/or in
money paid to AWS) is not really worth it for CI. In build2 we have
a fixed set of dedicated CI machines (hosted in our office, which
makes it even cheaper than Hetzner, long-term). Their background job
is to continuously rebuild packages in our repository (in particular,
this detects regressions due to new versions of dependencies). But
if there is a CI job, then it takes priority over the background
rebuilds. Adding a new CI machine is basically a matter of procuring
the hardware since the host OS image boots over the network and
requires minimal per-machine setup.

Another thing to keep in mind is that for certain targets, most
notably Mac OS, you are restricted to specific hardware you can
run them on (legally, in case of Mac OS). For example, while AWS
provides auto-scaling for Apple hardware, it's on the 24-hour
minimum allocation period (to comply with the Apple license). Being
able to "drop down" all the way to running own hardware on premises
is the only guaranteed way of handling such cases.