ffmpeg HIGH cpu usage while streaming

Hi Folks,

I have a streaming and recording script for an embedded ARM7 SoC. It's done under Yocto Project. The issue is the intense CPU usage around 97-100% for 1 core out of 4. Do you have any idea how could I distribute the streaming task over the 4 cores? I've been testing with -threads 4 ffmpeg option, with not much success. I double checked the Yocto recipie file, and ffmpeg was compiled with multi threading feature and to arm7 architecture.

here is the script:
Code:#!/bin/bash

if [ ! -e $(uci get application.audio.ffserver_config) ];then
cat > $(uci get application.audio.ffserver_config) <<EOF

HTTPPort $(uci get application.audio.streaming_port)
HTTPBindAddress 0.0.0.0
MaxHTTPConnections $(uci get application.audio.max_http_conns)
MaxClients $(uci get application.audio.max_clients)
MaxBandwidth $(uci get application.audio.max_bandwidth)
CustomLog $(uci get application.audio.ffserver_log)

<Feed audio.ffm>
File /tmp/audio.ffm
FileMaxSize 32M
</Feed>

<Stream audio>
Feed audio.ffm
Format wav
AudioCodec pcm_s16le
AudioBitRate 256
AudioChannels 2
AudioSampleRate $(uci get application.audio.streaming_sample)
NoVideo
StartSendOnKey
</Stream>

<Stream stat.html>
Format status
</Stream>
EOF
fi
#
ffserver -f $(uci get application.audio.ffserver_config) &
#
sleep 1

mkdir -p $(uci get application.audio.recording_path) || exit 1

mkdir -p $(uci get application.audio.recording_path)/$(date '+%Y-%m-%d') || exit 1

ffmpeg -f alsa -i hw:0,0 -acodec pcm_s16le -f segment -strftime 1 -segment_time $(uci get application.audio.duration) -segment_format wav -ar $(uci get application.audio.recording_sample) $(uci get application.audio.recording_path)/$(date '+%Y-%m-%d')/%Y-%m-%d__%H_%M_$(uci get application.audio.recording_sample)_$(sed 's/://g' /sys/class/net/eth0/address).wav -shortest http://localhost:$(uci get application.audio.streaming_port)/audio.ffm