Oracle Audio Technologies B31679-01 manual Other changes Large data stores

Other changes

Large data stores

access 12 data stores, add the following line to /etc/system and reboot before using TimesTen:

set shmsys:shminfo_shmseg=12

Other changes that you may need to make to your Solaris system include the following:

•To allow a large number of connections to a data store, add the following lines to /etc/system and reboot before using TimesTen:

set rlim_fd_cur=4096 set rlim_fd_max=4096

•To enable large shared memory objects in Solaris, add the following line to /etc/system and reboot before using TimesTen:

set shmsys:shminfo_shmmax = 0x240000000

Note: The value 0x240000000 (a 24 followed by seven zeroes) indicates that the largest shared memory segment that can be created is 1024 MB. The size of the shared memory segment required for a data store is larger than the data store size permanent size. Set this value high enough to support the largest shared memory segment needed.

If you keep data stores on a Solaris UFS file system, and are using transaction-consistent checkpoints, you may need to change the settings of some kernel parameters to get the best performance for your checkpoints. The Solaris UFS Throttle algorithm causes processes that write a single large file to be put to sleep when a byte count threshold exceeds the high-water mark. To disable the algorithm, add the line:

set ufs:ufs_WRITES = 0

to the /etc/system file.

Alternatively, you can increase the high-water mark by adding the line:

set ufs:ufs_HW = desired value

to the /etc/system.file

You must reboot the system for the new value to take effect.

Setting the high-water mark to the size of the checkpoint file should provide satisfactory performance, although a lower value may as well. More information on the UFS Throttle algorithm may be obtained in the white paper, “Understanding Solaris Filesystems and Paging” (SMLI TR-98-55) available from http://www.sun.com.

32Oracle TimesTen In-Memory Database Installation Guide