Need help with ASYNC_NETWORK_IO

We have a SQL Server 2005 server that is serving up 20 websites, one of which is our custom CMS, and a few other micro sites. I am new to this and just started looking at the databases here.

The problem is that we are having issues with the SQL Server slowing down after a few days which causes us to restart the service. I did some stats with the SQL Profiler but after review I didn't see anything that stuck out. This is why I am here now. I looked around online and came across ASYNC_NETWORK_IO. So, I am trying to follow this track now.

This is what I've done:

I cleared out the wait stats table.

DBCC SQLPERF ('sys.dm_os_wait_stats', 'CLEAR')

Results for the last 15 minutes:

ASYNC_NETWORK_IO    46798     34953     812     1953
CMEMTHREAD          28300     42328     1187    6437
CXPACKET            361571    7048515   38984   48859

From what I've read ASYNC_NETWORK_IO has to do with SQL waiting for the client application.

2 questions:

1) Is my assumption correct that these numbers seem high for 15 minutes of monitoring?

2) Where do I go from here? What should be my next step?

I'm trying to learn how this stuff works and I understand this is something I'm going to have to keep digging in to.

A push in the right direction would be great.

Reboot the offending client. Simple.

ASYNC_NETWORK_IO causes the server to slow down because the client can't consume data quick enough: the network buffers fill up.

FYI: CXPACKET is expected with parallelism. Not sure of current state but IIRC excess of there can be caused by hyperthreading.

Have you rebooted the client yet...? :-)

StackExchange Database Administrators Q#3332, answer score: 5