What is Physical Disk

 MaxCmds actually serves the same purpose as the MaxMpxCt on the Fileserver. Not surprisingly these two parameters have a special relationship. It’s like this: whenever an SMB session is setup (i.e. a shared file is accessed), the SMB session is negotiated. During this negotiation the Fileserver passes down the value of MaxMpxCt to the client (a Terminal server for example). The client then compares this value to his own MaxCmds value. The lower of the two values then is used to set a maximum on the number of outstanding client requests to the File server.

Possible values: 1-65535

MaxThreads
The MaxThreads specifies how many threads are allowed to run at once. (Each thread allows one outstanding operation.) By increasing this you can increase the amount of simultaneous work. Each extra execution thread will take 1 Kbyte of additional NonPaged pool memory.

Possible values: 1-255

MaxCollectionCount
Specifies the amount of data that must be present in the buffer of the redirector to trigger a write operation. If the amount of data in the buffer meets or exceeds this value, then it is written immediately. Otherwise, it is retained in the buffer until either more data is added or the value of the CollectionTime entry expires.

Possible values: 1-65535

Monitoring
Problems stemming from poor fileserving performance can sometimes be a bit tricky to pinpoint. One way to make sure is by using good ol’ perfmon. The problem with interpreting perfmon counters is that you can never know what the "right" value is unless you have baselined your environment properly. So what to monitor and how to interpret those values is entirely up to you. However, there are some counters you can monitor that I can give some basic tips on. Configure perfmon to monitor the following counters:

Physical Disk
You can measure this on the Terminal Server as well, but you should start at the file server. If the queue length is more than one for a sustained period of time, then your disks are hyperventilating. Give them some air: up your I/O throughput. Look on the software-side: are you paging a lot? (that'll kill your I/O throughput right there) or is your system disk heavily fragmented? Or on the hardware side: buy faster disks (15K SCSI) or upgrade your RAID controller.

know more : ms lan manager