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SAP Note

Header Data

Symptom

Inability to open files, open client/server connections, open DBMS connections, etc.

For example, the following error message keeps reoccurring in the MDS log files:"RuntimeEnvironmentFileAccessorDisk::ModEnvValue: pointer to stream is NULL; the file(/usr/sap/P16/MDS00/config/mds.ini) failed to be opened."

Other Terms

MDS

Reason and Prerequisites

File descriptors are used when opening sockets, files, and many other system objects that requireaccess via handles.

Some UNIX platforms have a low default value for the maximum number of file descriptors availablefor a process.

When there is a very high load on MDM, or if a stress test is being performed, the above symptom mayoccur.

The OS default values for the maximum number of file descriptors are:Solaris: 256Linux: 1024AIX: 2000HP-UX: 2048

This does not apply to Windows platforms.

When the number of available file descriptors is lower, the chances of the above mentioned problemis higher.

Solution

The number of file descriptors allowed per process should be changed on AIX, HP-UX and Solaris

systems to 8192. To apply this change, use one of the following platform-specific administrativeutility tools:

- For AIX, use smitty to change the file-max parameter.- For HP-UX, use smh to change the file-max parameter.- For Solaris, use smc to change the rlim_fd_max parameter.

Note:The number of file descriptors on AIX, HP-UX systems can be changed at runtime; however this is notthe case on a Solaris system.

The default number of file descriptors allowed per process should not be changed on Linux systems.The maximum number of file descriptors allowed per process is 1024 on Linux, and increasing thisvalue could cause the MDM application to crash. As a result, the above mentioned error occur in MDMwhen the applications are being stress-tested.

On HP-UX, the number of file descriptors allowed per process is 8192 starting from MDM 7.1 SP06Patch 27 (see SAP note # 1577797). For prior MDM versions running on HP-UX, the maximum numbersupported is 2048.

The affective ulimits are written by MDS during startup into the trace file nohup.out at MDS \workfolder.To check ulimit settings at the recent startup, search for the last trace line which starts with"Starting". Current MDS ulimits are reported under that line.

1522123 - File Descriptors Availability

Version 14 Validity: 14.04.2013 - active Language English

Released On 14.04.2013 11:38:51Release Status Released for CustomerComponent MDM-FN-MDS Master Data Server

MDM-FN Master Data Management FoundationPriority Recommendations / Additional InfoCategory Consulting

Other Components

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