Marian M. said:
Is there a regedit way to change the file sharing lock count in Vista? The
MS
article 815281 must be giving directions for XP. I don't see
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\Jet 4.0, or even
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet, in my machines registry. I'm
nervous about using VBA to do this.
Hi Marian,
I don't have a complete answer, but I'd make a couple of observations ...
First, the "file sharing lock count" is a function of Access, and/or the Jet
Database Engine (which is at the heart of Access). It's not an aspect of
Vista, or an operating system function, as such.
Second, I get worried when I see folks changing this value. Changing it is
almost never required. But it often implies the user has some kind of
performance or stability problem which they are trying to solve, and they've
discovered this setting as a possible solution. So my questions are:
- do you have an Access database file sitting on a Novell Netware file
server? and
- do you have more than, say, 50 users concurrently accessing that
database? Not just using the database, but all reading and updating the mdb
file, at the very same moment?
If the answer to either is "no", it is unlikely you need to change this
value. The default MaxLocksPerFile is 9500 - which is high enough for most
scenarios, outside very heavy-duty, shared database applications (with 50
concurrent users, that's 190 locks per user).
Possibly you're having some kind of performance or stability problem with
Access, or a Jet-based application? If so, the problem is probably not
related to MaxLocksPerFile. If the mdb file is sitting on a Vista machine,
and is being accessed from other Vista machines, you'll want to be aware of
this known issue:
http://support.microsoft.com/?kbid=935370
There's currently no solution. Note that Access generally runs fine, when
the app and the database file are both on the same machine (the most common
scenario). The 935370 issue only arises when the database file is shared
across the network.
If you're trying to adjust this value because you're following the
instructions in a README or similar doco then, those instructions are
probably wrong, or out of date. If you're having a problem running Access,
you'd better describe the "real" problem, so we can suggest the right
solution (since MaxLocksPerFile probably isn't the right answer). Actually,
you'll probably get better results asking in an Access group like
microsoft.public.access, since the Access experts will have more experience
and ideas, even if the underlying cause is actually a Vista issue.
(If you have analysed a performance problem in your database application and
determined that you are, in fact, seeing transactions aborted due to
insufficient locks, then ... my apologies, for being a patronising git!
As to why you don't see that value in your registry ... er, I dunno. I can
see it on my machine, which has Access 2007 installed. Maybe you're running
64 bit Vista? In which case, the key will actually be at:
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Jet\4.0
.... because Access is a32-bit application.
Hope this helps!
