How to best test this?

[probonopd]

Is there a "known good" test with a real-world server on the net that can be used for testing?

E.g., how can this be used to update an Ubuntu ISO.
https://help.ubuntu.com/community/ZsyncCdImage

[lslvr]

Here we have a bunch of files that could be used to test: https://repo.nxos.org/ubuntu/iso/.

[azubieta]

@probonopd I just added a benchmark for testing the algorithm that can be found here

libzsync-go/zsync_bench_test.go

Line 50 in 8cbf13d

func BenchmarkZSync2_SyncAppImageTool(t *testing.B) {

I have been working on the performance but still is under-performing, it's usable for file < 200 Mb. With larger files it's just too slow.

If you want to make you're own testing please check the test and benchmarking files in the project root.