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BDB performance issue

Hi All,
I'm a newbie with bdb - and I have a server not performing well - openldap shows high cpu usage and iowait of server is high. So I got stats of bdb but I'm not sure what to make out of it.  With help of google I could see that the basic parameters like requested pages and locks are ok. But there are other parameters which are suspect.
The output of db_stat -c is as follows :

196     Last allocated locker ID
0x7fffffff      Current maximum unused locker ID
9       Number of lock modes
1000    Maximum number of locks possible
1000    Maximum number of lockers possible
1000    Maximum number of lock objects possible
25      Number of current locks
758     Maximum number of locks at any one time
163     Number of current lockers
167     Maximum number of lockers at any one time
25      Number of current lock objects
394     Maximum number of lock objects at any one time
3609M   Total number of locks requested (3609996536)
3609M   Total number of locks released (3609996497)
0       Total number of locks upgraded
50      Total number of locks downgraded
3054935 Lock requests not available due to conflicts, for which we waited
0       Lock requests not available due to conflicts, for which we did not wait
14      Number of deadlocks
0       Lock timeout value
0       Number of locks that have timed out
0       Transaction timeout value
0       Number of transactions that have timed out
712KB   The size of the lock region
187M    The number of region locks that required waiting (56%)


The output of dbstat -m is ( which looks ok to me )
1GB 869MB 672KB Total cache size
1       Number of caches
1       Maximum number of caches
1GB 869MB 672KB Pool individual cache size
0       Maximum memory-mapped file size
0       Maximum open file descriptors
0       Maximum sequential buffer writes
0       Sleep after writing maximum sequential buffers
0       Requested pages mapped into the process' address space
1535M   Requested pages found in the cache (99%)
247743  Requested pages not found in the cache
5517    Pages created in the cache
247743  Pages read into the cache
3491659 Pages written from the cache to the backing file
0       Clean pages forced from the cache
0       Dirty pages forced from the cache
0       Dirty pages written by trickle-sync thread
253260  Current total page count
253253  Current clean page count
7       Current dirty page count
262147  Number of hash buckets used for page location
1535M   Total number of times hash chains searched for a page (1535296125)
4       The longest hash chain searched for a page
1245M   Total number of hash chain entries checked for page (1245967353)
31M     The number of hash bucket locks that required waiting (0%)
30M     The maximum number of times any hash bucket lock was waited for (1%)
13566   The number of region locks that required waiting (4%)
0       The number of buffers frozen
0       The number of buffers thawed
0       The number of frozen buffers freed


Are the lines in red really prbs or just side effects ? How do I go abt it ?

Thanks and Regards,
Amol.