Write and X Request at ~17kb
Hi, i have a problem, i don't know where to look at anymore. Installed are a 2003 and a W7 PC. Connected via Gigabit Switch. If I copy a file, the copy speed depends on who initiates the file transfer. For example, I try to copy a File from the W7 to the 2003 PC: If i logon to the W7 PC and copy a file from C:\File to \\2003\c$\File it copys with 20 MB/s If i logon to the 2003 PC and copy the same file from \\W7\c$\File to C:\File it copys with 50 MB/s It is the same file, the same source and the same destination. But even if I change the copy direction (from 2003 to W7) the problem is the same. Wireshark tells me, that if the 2003er initiates the transfer,every 61440 bytes a Read and X Request ist made. SRC: 192.168.178.2 DST: 192.168.178.42 SMB Read AndX Request, FID: 0x4001, 61440 bytes at offset 648081408[/CODE] http://666kb.com/i/blyth5lm42idezl71.jpg If the W7 PC initiates the transfer,every 16580 bytes a Write and X Request ist made SRC: 192.168.178.2 DST: 192.168.178.42 SMB Write AndX Response, 16580 bytes[/CODE] http://666kb.com/i/blythsey3mkpqgtn1.jpg In my researches i noticed, that if i set jumbo frames to 4 kb, only 4 pakets are transmitted, what sounds like TCPWindowSize: http://technet.microsoft.com/en-us/library/cc938219.aspx >> For Ethernet networks, the default value of this entry is 0x4470 (17,520 , or 12 segments of 1,460 bytes each). >> For other networks, the default value is 0xFFFF >>(65,535) unless 0xFFFF is larger than: Another thing i noticed is, that the transfer from W7 to the 2003er starts with ~90 MB/s, then (after 1-2 seconds) drops down to ~50 MB/s, then (after 2 more seconds) to 30 MB/s, and then lowers continuous to 20 MB/s. This takes about 30 seconds. What i've tried so far: - Drivers are all new (from 2010) - Everything fully patched - No Firewall, No virusscanner - different copy tools (KillCopy, TeraCopy) - On the 2003er TCPWindowSize to 65535 (RegKey, TCPIP\Parameters\Interfaces...) - On W7 added ctcp, and - autotuninglevel: enabled/disabled/normal - Changed a lot of Network Adapter Settings, such as Jumbo Frames ans puffer sizes ... but all with no success. Is this even the right point to look at? Can this be the source of the problem? Whose TCPWindowSize is used when an connection is started? Do i have to look at the W7, or at the 2003 PC? Thank you so far! best regards Alexander Schnitter
August 21st, 2010 10:38am

Hi, I put a new HDD in the 2003er and installed Server2008 on it. Without any configuration or else I copied with 50MB/s. The 2003er stills copys with 20MB/s :( So I think it depends on the 2003er server, but still don't know where to look anymore... Thanks so far
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August 29th, 2010 4:23pm

*BUMP* Any updates here? I have having the same issue. Thanks!
July 5th, 2011 3:25pm

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