When you access files over a network, you may sometimes
notice a small delay.
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This problem occurs because the current redirector code in
Windows XP performs certain operations that may affect performance when you
access files over a network.
The Windows XP redirector currently
performs the following behaviors that can affect performance:
| • | The redirector does not cache directory contents for a long
time.
This may affect performance where there are a lot of FindFirst("*") calls. |
| • | The redirector disables collapsing on the file handles of files that have been extended so that
directory information can be updated on the server more quickly.
This
may affect performance when a file is being opened after having been
extended. |
| • | The redirector tries to close delayed closes when Read-Attribute-Only open operations occur for that file.
This is to prevent
a sharing violation from occurring on the server. This may affect performance
because it is an unnecessary operation. A sharing violation does not occur for Read-Attribute-Only open operations. |
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Service pack information
To resolve this problem, obtain the latest service pack for Windows XP. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
322389 (http://support.microsoft.com/kb/322389/) How to obtain the latest Windows XP service pack
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Hotfix information
A supported hotfix is now available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next service pack that contains this hotfix.
To resolve this problem, submit a request to Microsoft Online Customer Services to obtain the hotfix. To submit an online request to obtain the hotfix, visit the following Microsoft Web site:
Note If additional issues occur or any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. To create a separate service request, visit the following Microsoft Web site:
File information
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the
Time Zone tab in the Date and Time tool in Control Panel.
Date Time Version Size File name Platform
------------------------------------------------------------------
03-Dec-2002 19:34 5.1.2600.1147 399,488 Mrxsmb.sys
03-Dec-2002 19:34 5.1.2600.1147 154,752 Rdbss.sys
03-Dec-2002 19:35 5.1.2600.1147 1,256,192 Mrxsmb.sys IA-64
03-Dec-2002 19:35 5.1.2600.1147 488,704 Rdbss.sys IA-64
This update performs the following:
| • | It adds an opportunistic directory cache to the Server
Message Block (SMB) mini-redirector.
This improves performance by
trying to cache the contents of a folder when a FindFirst("*") call occurs, and the network share where the folder resides has
the unique name bit exposed.
Note You can override this new setting by setting the
DisableDirectoryCaching registry value to a non-zero
value. To find the DisableDirectoryCaching registry entry, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\lanmanworkstation\Parameters\ . |
| • | The redirector now sets a bit on the Fobx (the user handle)
that indicates it has extended the file when it performs a write operation that
extends the file.
When that Fobx is closed, the redirector tries to
send a Set-End-of-File command to the server to alert it to update directory
information. |
| • | The redirector no longer follows the code path to close a delayed close when a Read-Attribute-Only open operation occurs. |
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Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Microsoft Windows XP Service Pack 2.
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After you install this update, performance benchmarking
utilities such as Netbench may show a throughput increase of up to 21 percent.
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