<html><head><meta http-equiv='Content-Type' content='text/html; GB2312'><style type='text/css'><!--.style3 {color: #0072A8}--></style></head><body bgcolor='#FFFFFF' topmargin='5' leftmargin='5' rightmargin='5' bottommargin='5' marginwidth='0' marginheight='0'><BR><BR>Hi guys:<BR> Last mail has some format problems,and i'm sorry for that .<BR><!-- --> I use wireshark to capture data at 480Mbps and found packets lost when wireshark indicate that "Drop" is zero and "Receive but no buffer" is not zero. <BR><!-- -->So I learned the sourcecode of wireshark and winpcap, found that "Receive but no buffer" in wireshark come from PacketRequest() in packet32.dll using DeviceIoControl() and the function code is "OID_GEN_RCV_NO_BUFFER", which MSDN explains as follows:<BR><BR>As a query, the OID_GEN_RCV_NO_BUFFER OID specifies the number of frames that the NIC cannot receive due to lack of NIC receive buffer space. Some<BR>NICs do not provide the exact number of missed frames; they provide only the number of times at least one frame is missed.<BR><BR>Is that means my NIC hardware buffer is too small?<BR>Can i improve reading speed by recompiling npf.sys to fix this problem?<BR><!-- -->If i use packet.lib, what should i do to make read operation more fast besides decrease value of mintocopy ?<BR><!-- --><BR><!-- -->Here are some information of my laptop: WinXp sp3, NDIS5.1, dual CPU at 2GHz, 2G memory, Realtek RTL8168C(P)/8111C(P) PCI-E Gagibit Ethernet NIC<BR><!-- --></body></html>