Applies to

Version(s)

4.0

Problem

Mac volume locks up accessing files on NT4.

Causes and Workarounds

The following are three possible causes and workarounds:

1. The prime suspect has to do with searching or moving large MacVolumes on NT4. If an administrator type account/client (like Araxi for example) is asking for a "DIR /S *.*" type of information from a large MacVolume it may fill up the circular log file on NT. If that happens, the system hangs until the file is flushed from the RAM to the disk. This is especially true if the volume in question is more that a few GB in size and if it has a couple of tens of thousands of files/folders (just like we have only we have it even bigger).
   The proposed fix is to go to the registry and add a value in: HKLM/SYSTEM/currentcontrolset/control/FileSystem
   We need to add the following entry:
   Value Name: NtFsDisableLastAccessUpdate
Data Type: REG_WORD
Data: 1
2. AFP Indexing: it seems likely that the SFM will index the MacVolumes only on startup, but the symptoms sound very close to what we are seeing in this case. SFM is using only non paged pool of memory for indexing purposes. If it runs out of memory during the indexing, it slows down or hangs entirely. This could be a long hang-up. The way to catch this is to watch for Memory/pool/Nonpaged Bytes counter in Performance monitor. Apparently, if a constant increase in non-paged pool bytes occurs over 20-30 minutes period of time, resulting in a large amount (20 to 30MB or more) of non paged pool you may be experiencing this problem.
   If this is indeed the problem, we should increase the value for: HKLM/system/currentcontrolset/services/macfile/parameters/nonpagedmemlimit.
   The default value is 4000 (decimal) and we should double it to see if the problem goes away. Of course, this may slow down other system resources but it will show us whether this is the problem or not.
3. CatSearch: it is possible that the Finder is calling for CatSearch when logging on or cataloging the MacVolume content. If it is, the server will do the catalog search and all the Macs will appear to be very busy network-wise. But, because this is a legit operation nobody times out or gets kicked out. To fix this we should go to: HKLM/system/currentcontrolset/services/macfile/parameters/Volumes
   Once there, we should pick the volume they we want affected (in our case an AraxiVolume) and add a multistring entry there, just like in the exercise 1). The multistring should state: disablecatsearch=1. After the alteration we should restart the sfmsvr (or reboot the machine). This may also have adverse effect on network performance. If an application (like Finder) starts using FindFile (client based operation) instead of CatSearch (server based and now disabled), that can aggravate the problem. Luckily, all of the above is easily fixable and reversible with no consequences. As a side note, further in the same article, MS claims that regardless of the value for disablecatsearch, AppleScript can fire a catsearch.

Technical Contact(s)

Sinisa Nojkovic

Date Submitted

17 Oct 2000