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Kernel Parameters for Macintosh
The Unix MediaAgent/iDataAgent software uses Unix/Macintosh kernel resources such as shared memory and semaphores extensively to facilitate inter-process communications and stream management. If the parameter settings within the CommCell components for these and other items are insufficient, various operations (such as data protection, data recovery, etc.) may fail. The more data that you can store in memory, the more efficiently will these operations run. Besides maintaining the data in memory, the Unix/Macintosh kernel significantly reduces disk input/output (I/O) activity.
The following sections and associated procedures discuss the recommended kernel parameter requirements for a typical environment based on the Unix/Macintosh system version. In effect, the requirements presented pertain to the appropriate Unix/Macintosh File System iDataAgent and/or MediaAgent. Note that the requirements specified for the resources needed by the CommCell components do not take into consideration any additional resources needed by any other application. Therefore, systems that interact with an application (e.g., Oracle) may require additional resources. These items should be (or should have been) administered by the appropriate application administrator.
Be sure to review the appropriate kernel parameter settings to ensure that they meet the software requirements. If you do not do this, you may encounter operation errors after installation. If you previously tuned your kernel parameters to levels that meet your application needs, continue to use the identified values. However, if you do change any kernel settings, be sure to restart the system unless otherwise indicated in order to activate the new settings.
| You do not need to set kernel parameters for AIX, FreeBSD and IRIX systems. |
To update the kernel parameters for HP-UX, you can use the System Administrator Menu (SAM). Use the ipcs command to obtain a list indicating the current shared memory and semaphore segments for the appropriate systems and their identification number and owner. See Set Kernel Parameters for HP-UX for step-by-step instructions.
To update the kernel parameters for Linux, you can use the /proc file system. Use the ipcs command to obtain a list indicating the current shared memory and semaphore segments for the appropriate systems and their identification number and owner. See Set Kernel Parameters for Linux for step-by-step instructions.
Kernel parameters for Macintosh are automatically configured via the install script for the Macintosh File System iDataAgent. We recommend that you do not change these parameters manually. Nonetheless, the procedure for changing the parameters manually along with the range of prescribed values for each kernel parameter are provided. See Set Kernel Parameters for Macintosh for step-by-step instructions.
To update the kernel parameters for Solaris versions up to and including Solaris 9, you must change the kernel parameter settings in the /etc/system file. Use the ipcs command to obtain a list indicating the current shared memory and semaphore segments for the appropriate systems and their identification number and owner.
If you had previously updated the /etc/system file, you probably need not update it again. However, if you do change the kernel parameter settings, be sure to save the /etc/system file and then reboot the system.
During the installation, you are given the option of letting the installation modify the /etc/system file for you. However, you might want to make your own updates. To this purpose, a reference file is created to guide you to make those changes, and the location of this file is specified at the end of the installation.
Solaris 10 kernel resources are monitored by resource controls. Resource controls allow you to modify kernel resources while the system is running. For Solaris 10, you can change the kernel resources dynamically by using the projmod command or the prctl command before or after the iDataAgent install. Information on Solaris 10 resource controls is located at http://docs.sun.com/app/docs/doc/817-1592/6mhahuoh1?a=view. See Set Kernel Parameters for Solaris for step-by-step instructions.
To update the kernel parameters for Tru64, you can edit the /etc/sysconfigtab file. See Set Kernel Parameters for Tru64 for step-by-step instructions.