Sybase ASE implments two page sizes: a virtual page size and a logical page size. The virtual page size is at the disk-level, and is always 2K (2048); the logical page size is 2k - 16k; this is the setting which affects how data/rows are stored. Going with a 4k or 8k setting is best, if your server contains a typical mix of OLTP and reporting data.
-- Show virtual page size
select @@pagesize
go
-- Show logical page size
select @@maxpagesize
go
Related note regarding log I/O size: For an ASE transaction log, the I/O size by default is 2*(@@maxpagesize), or twice the logical page size. Thus when creating a cache for the transaction log, you'll need to configure a pool with the appropriate I/O size.
-- Configure a cache for transaction log. Server @@maxpagesize = 4K (logical page size) in this example.
sp_cacheconfig tlog_cache, "500M", logonly
go
sp_poolconfig tlog_cache, "400M", "8K"
go
-- Show the log io size to confirm it is 2*(logical page size)
sp_logiosize
go
The transaction log for database 'billings' will use I/O size of 8 Kbytes.
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