- Make sender send more data per iteration.
- Make receiver iterate more often while receiving.
Before this commit tox would send at maximum around 4MiB/s. With this
patch sustained speeds of up to 100MiB/s were observed on a
low-latency, high-bandwidth network.
As a consequence of iterating more frequently the receiver's CPU usage
is increased for the duration of the transfer. The data structures
used to represent friends and file transfers cause the sender code use
costly loops that do little real work. This patch makes this problem
more visible: the sender uses more CPU while sending.
Poor network conditions were simulated using the netem kernel
facility: $ tc qdisc add dev lo root netem delay 100ms 50ms \
loss 1% duplicate 1% corrupt 1% reorder 25% 50%
and no adverse behavior was encountered. Tests were conducted
using toxic using both UDP and TCP.
