C10k Tsung Gatling and PlayWS - scala

Question

I'm new in Load Testing, but I googled a lot and configured test system on Amazon.
The system consist of: the Websocket server, on Play framework, and some load testing machines. I tried such load testing tools: Tsung and Gatling.
My testing scenario: I create >10k users each of them connects to the server and start sending messages for each second. I tuned linux to handle more than 100k connections. I playaround with JAVA_OPTS for gatling (added more memory and ParallelGC usage). I playaround with akka on the server side to handle 100-300 dispatcher threads. I ordered 36 vCPU machine with 60 GB RAM and 10GBit channel for server machine.
But the result was the same Tsung and Gatling send near 10k messages per second from the one machine(I sent just text messages < 160Bytes).
Can someone explain me. Why I can't reach more than 10k concurrent users (1 message per second). And what am I doing wrong?
actor {
default-dispatcher = {
fork-join-executor {
throughput = 1000
parallelism-factor = 36.0
parallelism-max = 154
}
}
}
JAVA_OPTS="-Xmx3800m -Xms3800m -Xmn2g -XX:+UseParallelGC -XX:ParallelGCThreads=20"
Linux configs
sudo ulimits -n > 999999
sudo vim /etc/sysctl.conf
# General gigabit tuning
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 4096 16777216
net.ipv4.tcp_wmem = 4096 4096 16777216
#
# # This gives the kernel more memory for TCP
# # which you need with many (100k+) open socket connections
net.ipv4.tcp_mem = 4096 65536 16777216
#
# # Backlog
net.core.netdev_max_backlog = 65535
net.ipv4.tcp_max_syn_backlog = 65535
net.ipv4.tcp_syncookies = 1
# Controls IP packet forwarding
net.ipv4.ip_forward = 0
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 0
# Disable netfilter on bridges.
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0
# Controls the default maxmimum size of a mesage queue
kernel.msgmnb = 65535
# Controls the maximum size of a message, in bytes
kernel.msgmax = 65535
# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736
# Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_max_syn_backlog = 65535
net.ipv4.tcp_synack_retries = 5
net.ipv4.tcp_orphan_retries = 5
fs.file-max = 999999
net.ipv4.tcp_max_orphans = 819200
net.core.somaxconn = 65535
net.ipv4.tcp_congestion_control = cubic
I tested with 5 client machines and I found that the server side on play framework can handle 50k messages per second from 50k users. with such configuration. The problem is that one client machine can't send more than 10k mps from 10k users. Maybe someone know other load testing tools that can send more than 10k mps from 10k users.