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Title	Slow file I/O in Hyper-V based environment

URL Name	Slow-file-I-O-in-Hyper-V-based-environment

Article Number	000181972

Environment	Product: OpenEdge Version: 11.5 OS: Windows 2012 Other: Hyper-V virtualization

Question/Problem Description

OpenEdge based application has functionaility that by nature generates a large amount of file I/O (example: document archiving, report generation)
In specific Hyper-V-based environments, opening the output file becomes slower over time until system becomes unusable.
Issue can be traced to points in code where files are opened for output; eventually ABL client will stall on these lines for multiple seconds.

At times when performance is bad, copying files via OS command line also becomes equally slow.

Steps to Reproduce

Clarifying Information

Error Message

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Enhancement Number

Cause

Slow I/O was caused by issues with Trend Micro anti-malware, being used on affected site.
These issues are described in more detail in following pages:
https://support.citrix.com/article/CTX136680
https://community.spiceworks.com/topic/532509-slow-write-performance-on-guest-vms-on-hyper-v-2012-r2

Resolution

Trend Micro has provided a registry fix for this issue. Create the following registry on all the affected servers:

Add new DWORD Value as:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TmFilter\Parameters] "DisableCtProcCheck"=dword:00000001
This registry key avoids the matching of PID for the .tmp file in the close table. In this case, VSAPI deletes the entry from the close table and that resolves the performance issue related to searching.
The purpose of the key DisableCtProcCheck=1 is to disable the close table searching.

Using Registry Editor incorrectly can cause serious problems that might require you to reinstall your operating system. Progress cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

Workaround

Notes

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Last Modified Date	3/22/2017 7:14 PM

Slow file I/O in Hyper-V based environment

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