[Samba] WinNT offline file attribute

John E. Malmberg wb8tyw at qsl.net
Thu Apr 25 19:59:02 GMT 2002

Damir Dezeljin wrote:
 > John Malmberg wrote:
 >> The SMBD process must not make files with the offline attribute
 >> visible to clients that do not support it.  This means that SMBD
 >> must find out that information somehow.
 > No. This isn't correct. It is HSM product's thing to do triger
 > read/open/write events and then it can put processes (threads) which
 >  access files to sleep - HSM product must implement a kernel module
 > that has to triger open,... events. Client that doesn't know
 > anythink about offline attributes just try to open files to get file
 > icons.

That is exactly the problem.  The Windows Explorer on the older
platforms will try to open files that are shelved. That will bog down 
the shelving system.

 > This is the second problem, because WinNT LANMAN server has a pool
 > of processes and every connection to a LANMAN server got its own
 > thread. This behaviour has its benefits - you can block an
 > individual connection to LANMAN server whilest the second instance
 > of Windows explorer on the same client can stil browse the share (it
 > got its own thread) - samba asign 1 thread 1 client accessing a
 > single share - this cause that if the thread is put to sleep,
 > windows "hangs" until the thread is unsleeped (you can't start any
 > other Windows explorer, nor you can't use a windows explorer which
 > is already started) - workaraound is that you can close the three
 > browsing window in Windows explorer and you can browse only the
 > current folder.

I do not understand how any of this logic is relevant to the problem.

The reason that the Windows client causes a shelved file to be
inadvertantly opened is not important.  The number of threads involved
is not important to the problem either.

SAMBA's being single threaded per process is a totally different issue 
than the shelved attribute.

I can reproduce the problems that you are mentioning simply by putting a 
  CD-ROM changer on a Windows NT system.  No network involved at all.
If one Explorer window has to wait for the CD-ROMs to switch, all 
explorer windows will freeze until it is done.

wb8tyw at qsl.network
Personal Opinion Only

More information about the samba-technical mailing list