Installation and Initial Configuration 1-27
Logical Log Configuration GuidelinesLOGFILES
LOGFILES specifies the number of logical log files managed by OnLine.
The minimum number required for OnLine operation is three log files. The
maximum number is determined by the number of logical log descriptors
thatcan fit on a page. For a 2-KB page, the maximum number is about 60 log
files. The default value of LOGFILES is 6.
Select the number of logical log files after you determine a general size for
total logical log size and you select a size for each logical log file.
LOGSIZE
LOGSIZE specifies the size of each logical log file managed by OnLine.
Theminimum size for a single logical log file is 200 KB. The default value of
LOGSIZE is 500 KB.
Ageneral guideline for sizing the individual logical log files is derived from
the guideline for all logging space: the total disk space allocated to the
physical log and the logical log files should equal about 20 percent of all
dbspace dedicated to OnLine. The ratio of logical log space to physical log
space should be about 3:1.
The default values included in thetbconfig.std file adhere to the guideline
just described. The default value of LOGSIZE is 500 KB. The default value of
LOGFILESis 6. Total logical log size is 3,000 KB. The size of the physical log is
1,000KB. Total space devoted to the physical and logical logs is 4,000 KB. This
value meets the first criterion of 20 percent of the root dbspace, which is
20,000 KB. The strategy also meets the second recommendation to allocate
logging space in a ratio of 3:1, logical log space to physical log space.