How To Fix SY138 - Maximum permitted number of open files exceeded

SAP Error Message - Details

• Message type: E = Error

• Message class: SY - ABAP/4 system messages

• Message number: 138

• Message text: Maximum permitted number of open files exceeded

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message SY138 - Maximum permitted number of open files exceeded ?

  The SAP error message SY138, which states "Maximum permitted number of open files exceeded," typically occurs when the SAP system reaches the limit of open file descriptors allowed by the operating system. This can happen due to various reasons, such as a high number of concurrent users, excessive background jobs, or misconfigured file handling in the application.
  Cause:
  
  Operating System Limit: Each operating system has a limit on the number of file descriptors that can be opened by a single process or by the system as a whole. If this limit is reached, the SAP system cannot open any more files.
  High Load: A sudden increase in user activity or background jobs can lead to a spike in the number of open files.
  Resource Leaks: Poorly written custom code or third-party add-ons may not close file handles properly, leading to resource leaks.
  Configuration Issues: The SAP instance may not be configured to handle the expected load, leading to premature exhaustion of file descriptors.
  
  Solution:
  
  
  Increase File Descriptor Limit:
  
  On Unix/Linux systems, you can increase the limit of open files by modifying the /etc/security/limits.conf file. Add or modify the following lines:
  * soft nofile 65536
  * hard nofile 65536
  
  You may also need to adjust the system-wide limit in /etc/sysctl.conf or by using the ulimit command.
  After making changes, restart the SAP instance and the operating system if necessary.
  
  
  
  Check and Optimize Code:
  
  Review custom ABAP code and third-party add-ons to ensure that all file handles are properly closed after use.
  Use transaction ST22 to check for dumps related to file handling and analyze the code paths that lead to excessive file usage.
  
  
  
  Monitor System Load:
  
  Use tools like top, htop, or lsof to monitor the number of open files and system load. This can help identify if the issue is due to high user activity or background jobs.
  
  
  
  SAP Notes and Support:
  
  Check for relevant SAP Notes that may address this issue or provide patches for known bugs related to file handling.
  If the problem persists, consider reaching out to SAP support for further assistance.
  
  
  
  Related Information:
  
  Transaction Codes: Use transaction codes like SM37 (to monitor background jobs) and ST22 (to check for dumps) to gather more information about the system's state.
  Operating System Documentation: Refer to your operating system's documentation for specific commands and configuration files related to file descriptor limits.
  SAP Kernel Version: Ensure that you are using a supported and up-to-date version of the SAP kernel, as newer versions may have optimizations and fixes related to file handling.
  
  By addressing the underlying causes and implementing the solutions mentioned above, you should be able to resolve the SY138 error and prevent it from occurring in the future.