From: Andre Noll Date: Tue, 20 Apr 2010 09:51:31 +0000 (+0200) Subject: FEC: Change the default slice size from 1490 to 1472. X-Git-Tag: v0.4.2~9 X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=4e979d91dc967b241a0f034a5600447eb7826eef;p=paraslash.git FEC: Change the default slice size from 1490 to 1472. 1472 is the maximal possible size that does not result in fragmentation on networks with 1500 MTU size (1500 = 1472 payload + 8 UDP header + 20 IP header). This can be verified using tcpdump -nv -i eth0 udp The output must contain a zero offset value, and the "Don't Fragment" IP flag (DF) should be set. Thanks to Gerrit Renker for pointing this out. --- diff --git a/send_common.c b/send_common.c index 92c9ab3b..f931fdaf 100644 --- a/send_common.c +++ b/send_common.c @@ -477,7 +477,7 @@ int parse_fec_url(const char *arg, struct sender_command_data *scd) goto out; } /* use default fec parameters. */ - scd->max_slice_bytes = 1490; + scd->max_slice_bytes = 1472; scd->slices_per_group = 16; scd->data_slices_per_group = 14; ret = 0;