The VxFS intent log is allocated when the file system is first created. The size of the intent log is based on the size of the file system - the larger the file system, the larger the intent log. The maximum default intent log size for disk layout Version 6 and 7 is 64 megabytes.

With the Version 6 and 7 disk layouts, you can dynamically increase or decrease the intent log size using the logsize option of the fsadm command. Increasing the size of the intent log can improve system performance because it reduces the number of times the log wraps around. However, increasing the intent log size can lead to greater times required for a log replay if there is a system failure.

See the mkfs_vxfs(1M) and the fsadm_vxfs(1M) manual pages.