Log records can span physical log blocks, especially when you have large records. Spanned log blocks can, in isolated cases, perform faster than a normal single block. However, for most cases, it performs slower and is not recommended.
Note: The use of the LONG VARCHAR data type creates rows that are as long as the block size of the containing area. The block size of the longest-block sized area containing the LONG VARCHAR data type should be used in calculating the Log Area block size.
CA Datacom/DB determines the physical block size by dividing the logical block size specified (BLKSIZE= value) by the number of physical blocks specified (BLOCKS= value). Do not specify values that result in a physical block size larger than 32760 or smaller than 16384. Regardless of how large the physical log block is defined, a maximum of 254 records can reside in a block. This is pertinent only to Log Areas that span physical log blocks.
The logical block size specified must be evenly divided by the number of physical blocks specified and be large enough to hold two times the record size plus space for the element list and include several hundred bytes of control information.
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