Windows Delayed Write Failed errors

Hi,
We have setup a new Xserve G5 with OS 10.4.6 mainly for Windows file sharing to 30 or so PCs. The system has DNS running to resolve the server’s ServerName.local domain name. Windows services is setup as the PDC and workgroup master browser. The server is also setup as a Standalone server.

Drag and drop file transfers perform quite well, but Windows users get “Delayed Write Failure – file could not be saved to network path” intermittently. This occurs mainly when saving within Autocad 2004 and other applications such as Word.

We have set the following smb.conf and sysctl.conf options with limited improvement:

smb.conf:
large readwrite = no
socket options = TCP_NODELAY IPTOS_LOWDELAY SO_SNDBUF=16384 SO_RCVBUF=16384
client signing = disabled
server signing = disabled
oplocks = no

sysctl.conf:
net.inet.tcp.delayed_ack=0
net.inet.tcp.newreno=1
net.inet.tcp.sendspace=65536
net.inet.tcp.recvspace=65536
net.inet.tcp.mssdflt=1440
kern.ipc.maxsockbuf=524288
net.inet.raw.maxdgram=8192
net.inet.raw.recvspace=8192

Has anybody run into such an error or performance issues doing file serving to a Windows workgroup?

Thanks,
Edward