Originally Posted by
CATIII-NDB
I do not know about your Network Topology. Are the MTU Values optmised ?
I really really wish people hadn't been made aware of MTU values, as it gets trotted out so many times when it's not relevant.
FYI, the MTU (or Maximum Transmission Unit) is the maximum size a data packet can be forwarded onwards, and is used when deciding whether to fragment packets into smaller ones or not for transmission over routers etc. XP to 7 in a home environment is 99.99999% likely to be over a single LAN segment where the default will be 1500 bytes.
Much more likely in SD's case is going to be duplex issues, causing runts and shorts (retransmissions) when a NIC set to autonegotiate is unable to negotiate a safe pairing of transmission speeds and duplexing between it and the other end of the RJ45 (i.e. the switch), and ensuring that this was set to a specific value rather than "auto" in the NIC would go a long way towards troubleshooting this issue. The reason for which is that the RFC governing this portion of networking is/was always ambiguous, and so certain manufacturers make kit that negotiates one way, and other manufacturers make kit that negotiates another way, and ne'er the twain shall meet (unless you use gigabit which is ONLY full duplex, which is why it's quite useful!). A clear example of this is when you connect a Netgear switch to a 3com switch or a Broadcom NIC (although in the latter case the interpretation of the RFC is closer and so you get an intermittent slowdown rather than a flat 'no').
Once the above issue is out of the way, the next thing to tackle is the firewall, as that's the next thing sitting in the way of the network packets and their transmission (aside from the network cable itself - but then we assume that SD has that under control already). A quick test of disabling both firewalls and checking speed would enable you to see whether speed was being affected by this component or not.
Finally, the security component of where the file's coming from and going to are to be considered, since the filesystem needs to be able to read the SIDs and gain access to the relevant filestore on the receiving system, but this is unlikely to be the cause of the slowdown (and would only ever manifest itself in a single slowdown at the start or end of the transmission, and not for each file etc).
Hope that helps?
Mike.