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RTO.Initial = 1 second for TCP
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Authored by tuexen on Jan 24 2019, 5:18 PM.

Details

Summary

This patch reduces the Initial RTO from 3 seconds to 1 second as allowed by RFC6298.

We might want to change the backoff factors for SYN segments first. Without that the lifetime of SYN-cache entries might be too short. To be discussed on the bi-weekly transport telco.

Test Plan

Use the attached packetdrill srcipt:

Diff Detail

Repository
rS FreeBSD src repository
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Event Timeline

tuexen created this revision.Jan 24 2019, 5:18 PM
Herald added a subscriber: imp. · View Herald Transcript
rscheff_gmx.at accepted this revision.Jan 24 2019, 5:57 PM

Should be adding RFC6298 to https://wiki.freebsd.org/TransportProtocols/tcp_rfc_compliance too...
Good that RFC2988 is marked obsolete there already - but i think that is only tracking the RFC state, not the state of which RFC the stack mostly conforms to.

(Suggestion: after this change, have the RFC2988 line in the table, but with strikethrough, and add a new line for 6298.

I support this enhancement!

kbowling accepted this revision.Jan 24 2019, 9:07 PM
kbowling added a subscriber: kbowling.

We ran this configuration for a very long time at LLNW

This revision is now accepted and ready to land.Jan 24 2019, 9:07 PM
This revision was automatically updated to reflect the committed changes.