Specifies the amount of memory to use for a load into a LF index.
DBA permissions are not required to set this option. Can be set temporary for an individual connection or for the PUBLIC group. Takes effect immediately.
LF_BITMAP_CACHE_KB defines the amount of heap memory (in KB) per distinct value used during a load into an LF index. The default allots 4KB. If the sum of the distinct counts for all LF indexes on a particular table is relatively high (greater than 10,000), then heap memory use might increase to the point of impacting load performance due to system page faulting. If this is the case, reduce the value of LF_BITMAP_CACHE_KB.
This formula shows how to calculate the heap memory used (in bytes) by a particular LF index during a load:
Heap-memory-used = (lf_bitmap_cache_kb * 1024) * lf-distinct-count-for-column
Using the default of 4KB, an LF index with 1000 distinct values can use up to 4MB of heap memory during a load.