i create database environment in this way:

ret = dbenv->open(dbenv,
sz_full_dbhome,
DB_CREATE | DB_INIT_LOCK | DB_INIT_MPOOL |
DB_THREAD,
0);

the only parameter is how many databases i will create in the
environment, each database is stored as btree.

so, how to sizing the lock subsystem? the locks, lockers, lock objects?

and another problem is, when i set the locks, lockers, lock objects a
very big number, the __db.00x files are up to 2~3 hundreds megabytes!
can i reduce the file size?

Hi,

db_stat -c will help you monitor and size the lock table parameters.

http://www.sleepycat.com/docs/utility/db_stat.html

Your cache size may be set very large (just a guess) . You can use
some of the other db_stat command options to help determine environment
configuration settings.. Your environment configuration parameters
will determine the size of those files.

Ron

yes, the environment configuration parameters determine the size of
those files.
but when i close the environmnet, what save in those files? why so
large? can i reduce the size or delete them when close?

i have a simple test, that only create an environment and close it, but
set the max locks, lockers, lock objects very large, e.g, 1000000,
those file will be 300 megabytes!

Ron wrote:

I'm not sure I know what your goal is here. If you are concerned about
having an environment backing file and it's size after shutdown then
maybe you should consider some of the other options and look at the
benefits of each such as DB_PRIVATE. WHen the environment shuts down,
there are no backing files. Please review:

http://www.sleepycat.com/docs/ref/env/region.html

Why do you have a setting of lock objects (lockers/locks ) of
1,000,000?

What is your environment configuration? How large is your cache?

Ron

Because you want to load a large file into the database in a single
transaction? One record per transaction is often too slow, and
splitting the update into multiple transactions is sometimes not
really justified. Spending several hours on implementing
functionality which is only rarely used isn't that much fun.