From 6fbf21b4f0abb89049e724b3bd625458327b6a77 Mon Sep 17 00:00:00 2001 From: Adam Ierymenko Date: Fri, 8 Mar 2019 13:15:47 -0800 Subject: Use a smaller MTU, which should not impact throughput since 2800+overhead/2 still fits in two of these. --- include/ZeroTierOne.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/ZeroTierOne.h b/include/ZeroTierOne.h index 3f8ce8e4..36c29c96 100644 --- a/include/ZeroTierOne.h +++ b/include/ZeroTierOne.h @@ -102,10 +102,11 @@ extern "C" { /** * Default UDP payload size (physical path MTU) not including UDP and IP overhead * - * This is 1500 - IPv6 UDP overhead - PPPoE overhead and is safe for 99.9% of - * all Internet links. + * This is small enough for PPPoE and for Google Cloud's bizarrely tiny MTUs. + * A 2800 byte payload still fits into two packets, so this should not impact + * real world throughput at all vs the previous default of 1444. */ -#define ZT_DEFAULT_PHYSMTU 1444 +#define ZT_DEFAULT_PHYSMTU 1432 /** * Maximum physical UDP payload -- cgit v1.2.3