If you create a cache for the transaction log of a database, configure most of the space in that cache to match the log I/O size. The default value is twice the server’s logical page size (for a server with 2K logical page size, it is 4K, for a server with 4K logical page size, it is 8K, and so on). Adaptive Server uses 2K I/O for the log if a 4K pool is not available. The log I/O size can be changed with sp_logiosize. The log I/O size of each database is reported in the error log when Adaptive Server starts, or you can check the size of a database by using the database and issuing sp_logiosize with no parameters.
This example creates a 4K pool in the pubs_log cache:
sp_poolconfig pubs_log, "3M", "4K"
You can also create a 4K memory pool in the default data cache for use by transaction logs of any databases that are not bound to another cache:
sp_poolconfig "default data cache", "2.5M", "4K"
See Chapter 32, “Choosing the I/O Size for the Transaction Log,” in the Performance and Tuning Guide for information on tuning the log I/O size.
