> but in other cases the build time before even running tests is slow. In my experience, this is spot on. In the CI system I help run for testing graphics, a s

> but in other cases the build time before even running tests is slow. In my experience, this is spot on. In the CI system I help run for testing graphics, a significant amount of the CI time is spent: 1) fetching source code from external locations for all dependencies that need to be built for each test, and for the project itself 2) fetching source code from internal git cache to builders 3) compiling projects (ccache helps a LOT) 4) syncing built artifacts to shared storage (NFS) 5) testers sync artifacts (rsync) 6) testers run tests 7) results sync'd back to CI master 8) process results and display to developers (the processing and display of results also takes a few minute, since it's often over 1 million tests results to process). Many of the steps here are repeated multiple times, since we run multiple test suites across nearly 200 individual testers. Our we average around a 30 min turnaround time for results. Steps 2, 4, 5, and 7 take a surprisingly long amount of time, since internal network utilization depends on CI load (e.g. it could be running other CI jobs at the same time). We are constantly looking for ways to improve it. For some of the tests that run, the syncing of artifacts and results take longer than the tests that run on the tester.