Slowdown on high-load machines with 3000 sockets

Christian Schmid
2005-02-27T16:53:46Z

Hello.

The problem here is that starting with 3000 sockets, the syswrite locks more and more on the sockets
although the sockets are non-blocking. This just suddenly appears at around 3000 sockets. I have
raised min_free_kbytes to 1024000 and then it suddenly did not block anymore. I changed it down to
16000 again and id instantly locked again. Up to 1024000 and no locking. Now it starts blocking
again at 4000 sockets even with 1024000 min_free_kbytes, slowing everything down.... what could this
be? Its no network-problem. I have discussed this issue with netdev-people for 2 weeks. No memory
problem as well I suppose, its 8 gb ram with a 2/2 split...

This problem has been observed on a 2.6.10 kernel.

Please help. Thank you in advance.

Best regards,
Chris