Vertx websocket concurrent connection limitations

[Hari Poludasu]

Hi,

In our implementation, vertx framework is used in server module to create websocket server and accepts websocket connect requests from browser clients.

During performance testing with JMeter, we observed after accepting 3800 ESTABLISHED connections from clients, server not responding for new websocket connect requests.

Platform OS: Debian 

We tried tweaking system configuration by adding following lines in sysctl.conf file, but we are able to push the limit to 4700 concurrent connections only.

net.ipv4.ip_local_port_range = 1024 65535

net.ipv4.tcp_fin_timeout = 60

net.ipv4.tcp_tw_recycle = 1

net.ipv4.tcp_tw_reuse = 1

fs.file-max = 818493

net.core.rmem_max = 16777216

net.core.wmem_max = 16777216

net.ipv4.tcp_max_syn_backlog = 4096

net.ipv4.tcp_syncookies = 1

net.core.somaxconn = 1024

 

Can someone help us to identify the bottleneck in creating more concurrent connections?

We are actually looking to create some 20K connections on single node.

Regards,

Hari 

 

[Alexander Lehmann]

what is your ulimit for open files? (ulimit -n)

each socket connection uses at least one filedescriptor, if it has to open other connections or files probably more.

[Hari Poludasu]

We increased ulimit from default 1024 to higher value, by editing sysct.conf

current ulimit -u shows 63147

[ro...@WSX-10.54.164.223 ~]# ulimit -u

63147

Regards,

Hari

[Tim Fox]

This will be an OS limitation. Can't really help you other than say try and get an expert on your OS to tune it.

Also... there is some information in the performance tuning section of the documentation.

--
You received this message because you are subscribed to the Google Groups "vert.x" group.
To unsubscribe from this group and stop receiving emails from it, send an email to vertx+un...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.