I am trying to use Iris to optimize my game, since its a social experience and uses quite a lot of replicated data between players.
Iris appears to be working fine, however my log spams this line an absolute ton, and takes up hundreds if not thousands of lines. Any idea what this means and maybe how to fix it?
[2025.03.05-21.49.23:335][142]LogIris: Disallowed to write first packet in batch, with Iris this is not good!
Hi, the solution is to saturate the bandwidth, which is disabled by default. Add this in your DefaultEngine.ini
[SystemSettings]
…
net.Iris.SaturateBandwidth=1
that log means the batch filled before the first packet could take data, so Iris drops the write for that tick rather than splitting. on social maps with many replicated props it shows up as spam while the scene still looks fine.
[SystemSettings]
net.Iris.SaturateBandwidth=1
set the value above under SystemSettings in DefaultEngine.ini so the scheduler uses the full budget per connection, then watch LogIris for a few minutes. when the spam stops, tune MaxClientRate and the per actor update frequency next, since saturation only helps when the budget itself is sized right.
you can also look at Iris Readiness Kit, an Iris replication plugin that checks bandwidth and scheduler settings that trigger packet batch warnings under Iris: Iris Readiness Kit — Audit Your Project Before Enabling Iris Replication | Fab there’s a shorts playlist on iris filtering basics too: https://www.youtube.com/playlist?list=PLWrCzz951TwA