Who does the work during a "drag and drop" action ??

[Reini Wei]

hi all,
i want to know exactly, what happens, if a user is "dragging and dropping" a
(huge) file
from the fileserver (windows share)

questions:

does the server "push", does the client "pull" ? (NTFS5 on win2000), no FAT
what CPU is involved, server , client? (Server cpu has some peaks to 80%, i
dont want this..)
which effect has the Network card/ TCP stack / PCI bus ? (PCI 3COM Server
NIC)
SCSI or IDE Harddisk has a CPU-related effect,
(read/write speed are the same on a single drive)

are there ways to "tune" a Fileserver for his job (exept "optimize for
filesharing/applications in
file and printer sharing / inside network settings)

does somebody know exactly, what is going on during a explorer-filetransfer?
e.g. "preparing to copy".. etc..

thank you for your comments.

cheers
reini

 

[Mark Zbikowski \(MSFT\)]

If you're using the SMB server, then the server only sends over data that
the client requests. So, you could call it a "pull". Now, as to why the
CPU
peaks, here are some answers:
1. File is encrypted. At present the data is decrypted before transmission.
2. File is compressed. The data is decompressed before transmission
3. You have an AV program that's looking for a virus signature
4. There's PIO for getting data to/from disk (as opposed to DMA)

HTH.

 

[Reini Wei]

thank you, mark,
it surprises me (thought, SMB protocol transfers data, compressed or
not.since it is Protocol Level.., and Compression was implemented on NTFS
FileSystem Level.) and gives ma answers about "poor" file transfer
performande, complained by co-workers..
What i was trying to find, was the "bottleneck ", as a filetransfer is going
through
all 7 OSI Layers.. down and up..

(i was suspecting the network swich, but got proper transfer-speed values
from SNMP-counter)

in our case, compression, and AV, applies.. if one uses IDE PIO Mode, he
cannnot be helped ;-).. ok, some old 4xCD-Roms.. do this.. and it is a
"fallback" mode ..
hope, SCSI is ot affected by this. and if you take wrong IDE-cables.. you
could have unwanted effects..

hmm, i tought, a fileserver does not need much cpu...
(but AV, EFS and Compression changed this, i have to confess...)

also, during a long file-transfer (1 file, 20GB, uncompressed), the HD LED
does not show activity all the time, approx. 2sec activity, 1 sec. pause, 2
sek activity..and so on.
and the CPU goes like a Zigzag line in Taskmanager..

i was thinking, that the Server has to "wait" because of network speed,
client hdd read performance..and because of the client AV engine, too..

cheers
reini