[Samba] What makes excel file opening so slow??
Adam Tauno Williams
adamtaunowilliams at gmail.com
Thu May 31 17:56:11 GMT 2007
> Despite the question I asked last time (I will re-install the FC3
> with Samba 3.0.14a on another computer for replacement soon), I still
> have one more question on Excel files. I found that Excel file opening
> is extremely slow (especially on slow connections, i.e. VPN). The case
> is really bad, it takes around 2 mins to open a excel file of around
> 400k. Actually we got both side having 4M/4M DSL line.
Speed doesn't matter so much as latency. Check out some documents on
windowing, etc... maybe you can improve the efficiency of your link.
> However if we build a VPN
> inside Hong Kong, it takes 10~20 seconds to open a 400k excel file.
I don't understand what this means.
> However if I just copy a 400k file, neither of them take such a long
Ok, opening is not comparable to copying.
> Both situation can finish the transmission within some seconds.
> So what is so special about opening a excel file, and how can I
> improve the speed? Thanks for comments!
One would have to see a network trace, but I'd wager Excel is reading
the file in a manner that causes lots of round trips - then latency
kills you. I've seen this kind of thing before. Make sure oplocks are
enabled. If you really need to go faster maybe see if accessing the
file via WebDAV instead of CIFS/SMB is sufficient. We've found WebDAV
to be 'faster' over high-latency VPN links. But you get less fancy
locking (if any).
Adam Tauno Williams, Network & Systems Administrator
Consultant - http://www.whitemiceconsulting.com
Developer - http://www.opengroupware.org
More information about the samba