i use Python bsddb moudle
create env as above:
flags =
bsddb.db.DB_CREATE|bsddb.db.DB_INIT_TXN|bsddb.db.D B_INIT_MPOOL|bsddb.db.DB_THREAD|
bsddb.db.DB_RECOVER
dbenv = bsddb.db.DBEnv()
dbenv.open(self.__dbpath,flags)

create db:
db = bsddb.db.DB(dbenv)
db.open(self.filename,self.__listname,
bsddb.db.DB_HASH,
bsddb.db.DB_CREATE| bsddb.db.DB_THREAD)


after create some dbs(not the first time), the "DB.open" function never
return again,
i don't know how could this happen, this problem will make me crazy, I
use bdb in multi-thread, but it will let all my thread dead
immediately,
what's wrong with bdb?

I found what's wrong here. Deadlock occur while i use dbd in
multithread, all ok after i remove all thread flag and bsd env.
Now I provide thread-safe mechanism outside the python bsddb
module, But I can't ensure data is safe while program exit abnormally,
DBEnv's recover cant ensure too,
At last, I have to change my database, only use bdb to provide
cache