In: Redis, Out: Redis very slow since upgrade vom LS from 1.5 to 2.3.0

Hi,

i'm using logstash to transport logs from redis to redis.

`input {
redis {
host => "redis1.int.local"
port => "6381"
data_type => "list"
threads => 50
key => "logs"
type => "logs"
}
}

output {
if [type] == "logs" {
redis {
host => "redis2.int.local"
port => "6379"
data_type => "list"
key => "logs"
workers => 50
}
}

}`

With logstash 1.5 i could transfer >100.000 Messages per Minute between the redis nodes.
After the upgrade to 2.3 i'm not getting more than 1.000 Messsages per Minute.

I already played with the -w (1-250) and -b (1-8000) parameters, but without success.

The current parameters are:
LS_OPTS="-w 150 -b 100" LS_HEAP_SIZE="6g" LS_OPEN_FILES=163840 KILL_ON_STOP_TIMEOUT=1
All other parameters are the defaults from the logstash debian package.

Some additional information:
Network speed between redis1, redis2 and logstash node: 1Gbit
Redis Version: 3.0.7

Please help me to find the problem.

Thank you very much.

Robert