V
Valeriy Bashkatov
Guest
Yes, you understood correctly. I again checked this on the ATM database and here's the result. 1. I deleted all CDC policies and restarted the database. 2. After starting the database for the history1 table, I added one CDC policy, but did not activate it. I did this through the Pro2 Administration Utility. 3. Now in the promon menu R&D 1/13 Status: Shared Resources I see that I have 1 object in the Secondary object cache 09/14/18 Status: Shared Resources 16:59:34 Active transactions: 0 Lock table entries in use: 0 of 10016 Lock table high water mark: 10 Primary object cache (-omsize): Total: 1024 Used: 265 Pinned: 0 Secondary object cache (-omsize): Total: 1024 Used: 1 Pinned: 1 Primary MT cache (-mtpmsize): Total: 1024 Used: 0 Pinned: 0 Secondary MT cache (-mtpmsize): Total: 1024 Used: 0 Pinned: 0 Number of servers: 2 (41 allocated) Total users: 2 (200 allocated) Self-service: 0 Remote: 2 Batch: 0 Watchdog status: Executing BIW status: Executing Number of page writers: 1 Number of monitors: 2 Number of semaphores allocated: 249 Shared memory allocated: 852384K (1 segments. The last segment was not locked in memory) Enter , R, P, T, or X (? for help): 4. Now reset promon statistics in the promon menu R&D debghb 6/11 Activity: Latch Counts. And start this simple code: MESSAGE "Zero Activity: Latch Counts" VIEW-AS ALERT-BOX. /*manuale reset promon statistics and click OK*/ DEF VAR i AS INT NO-UNDO. i = 0. FOR EACH atm.history1 NO-LOCK: DISPL history1. PAUSE 0. i = i + 1. IF i > 10 THEN DO: LEAVE. END. END. MESSAGE "Update Activity: Latch Counts" VIEW-AS ALERT-BOX. 5. Update promon statistics in Activity: Latch Counts 09/14/18 Activity: Latch Counts 17:00:55 09/14/18 16:59 to 09/14/18 17:00 (1 min 26 sec) ----- Locks ----- ------ Busy ------ Naps ---------- Spins ----------- ----- Nap Max ----- Owner Total /Sec /Sec Pct /Sec /Sec /Lock /Busy Total HWM MTX -- 0 0 0 0.0 0 0 0 0 0 0 USR -- 6 0 0 0.0 0 0 0 0 0 0 OM -- 762 8 0 0.0 0 0 0 0 0 0 BIB -- 86 1 0 0.0 0 0 0 0 0 0 SCH -- 0 0 0 0.0 0 0 0 0 0 0 LKP -- 36 0 0 0.0 0 0 0 0 0 0 GST -- 0 0 0 0.0 0 0 0 0 0 0 TXT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 SEQ -- 0 0 0 0.0 0 0 0 0 0 0 AIB -- 0 0 0 0.0 0 0 0 0 0 0 TXQ -- 2 0 0 0.0 0 0 0 0 0 0 EC -- 0 0 0 0.0 0 0 0 0 0 0 LKF -- 54 0 0 0.0 0 0 0 0 0 0 BFP -- 0 0 0 0.0 0 0 0 0 0 0 BHT -- 1583 18 0 0.0 0 0 0 0 0 0 PWQ -- 0 0 0 0.0 0 0 0 0 0 0 CPQ -- 858 9 0 0.0 0 0 0 0 0 0 LRU -- 8 0 0 0.0 0 0 0 0 0 0 LRU -- 0 0 0 0.0 0 0 0 0 0 0 BUF -- 1954 22 0 0.0 0 0 0 0 0 0 BUF -- 434 5 0 0.0 0 0 0 0 0 0 BUF -- 348 4 0 0.0 0 0 0 0 0 0 BUF -- 430 5 0 0.0 0 0 0 0 0 0 INC -- 0 0 0 0.0 0 0 0 0 0 0 CDC -- 0 0 0 0.0 0 0 0 0 0 0 SEC -- 0 0 0 0.0 0 0 0 0 0 0 LG -- 0 0 0 0.0 0 0 0 0 0 0 Enter , A, L, R, S, U, Z, P, T, or X (? for help): As we can see, OM latch is now used very actively when only 10 records are read. 6. Now online I delete this CDC-policy via Pro2 09/14/18 Status: Shared Resources 17:03:27 Active transactions: 0 Lock table entries in use: 0 of 10016 Lock table high water mark: 10 Primary object cache (-omsize): Total: 1024 Used: 265 Pinned: 0 Secondary object cache (-omsize): Total: 1024 Used: 1 Pinned: 0 Primary MT cache (-mtpmsize): Total: 1024 Used: 0 Pinned: 0 Secondary object cache is still in use. 7. I execute my code again and look into Activity: Latch Counts 09/14/18 Activity: Latch Counts 17:04:14 09/14/18 17:03 to 09/14/18 17:04 (14 sec) ----- Locks ----- ------ Busy ------ Naps ---------- Spins ----------- ----- Nap Max ----- Owner Total /Sec /Sec Pct /Sec /Sec /Lock /Busy Total HWM MTX -- 0 0 0 0.0 0 0 0 0 0 0 USR -- 2 0 0 0.0 0 0 0 0 0 0 OM -- 762 54 0 0.0 0 0 0 0 0 0 BIB -- 14 1 0 0.0 0 0 0 0 0 0 SCH -- 0 0 0 0.0 0 0 0 0 0 0 LKP -- 8 0 0 0.0 0 0 0 0 0 0 GST -- 0 0 0 0.0 0 0 0 0 0 0 TXT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 SEQ -- 0 0 0 0.0 0 0 0 0 0 0 AIB -- 0 0 0 0.0 0 0 0 0 0 0 TXQ -- 2 0 0 0.0 0 0 0 0 0 0 EC -- 0 0 0 0.0 0 0 0 0 0 0 LKF -- 12 0 0 0.0 0 0 0 0 0 0 BFP -- 0 0 0 0.0 0 0 0 0 0 0 BHT -- 1569 112 0 0.0 0 0 0 0 0 0 PWQ -- 0 0 0 0.0 0 0 0 0 0 0 OM latch is still in use. 8. Again, activate the CDC policy and restart the database. 09/14/18 Status: Shared Resources 17:07:37 Active transactions: 0 Lock table entries in use: 0 of 10016 Lock table high water mark: 0 Primary object cache (-omsize): Total: 1024 Used: 265 Pinned: 0 Secondary object cache (-omsize): Total: 1024 Used: 0 Pinned: 0 Primary MT cache (-mtpmsize): Total: 1024 Used: 0 Pinned: 0 Secondary MT cache (-mtpmsize): Total: 1024 Used: 0 Pinned: 0 Now Secondary object cache is not used. 9. I execute my code again and look in Activity: Latch Counts 09/14/18 Activity: Latch Counts 17:09:35 09/14/18 17:09 to 09/14/18 17:09 (5 sec) ----- Locks ----- ------ Busy ------ Naps ---------- Spins ----------- ----- Nap Max ----- Owner Total /Sec /Sec Pct /Sec /Sec /Lock /Busy Total HWM MTX -- 0 0 0 0.0 0 0 0 0 0 0 USR -- 0 0 0 0.0 0 0 0 0 0 0 OM -- 0 0 0 0.0 0 0 0 0 0 0 BIB -- 0 0 0 0.0 0 0 0 0 0 0 SCH -- 0 0 0 0.0 0 0 0 0 0 0 LKP -- 4 0 0 0.0 0 0 0 0 0 0 GST -- 0 0 0 0.0 0 0 0 0 0 0 TXT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 LKT -- 0 0 0 0.0 0 0 0 0 0 0 SEQ -- 0 0 0 0.0 0 0 0 0 0 0 AIB -- 0 0 0 0.0 0 0 0 0 0 0 TXQ -- 2 0 0 0.0 0 0 0 0 0 0 EC -- 0 0 0 0.0 0 0 0 0 0 0 LKF -- 6 1 0 0.0 0 0 0 0 0 0 BFP -- 0 0 0 0.0 0 0 0 0 0 0 BHT -- 1641 328 0 0.0 0 0 0 0 0 0 PWQ -- 0 0 0 0.0 0 0 0 0 0 0 CPQ -- 52 10 0 0.0 0 0 0 0 0 0 Now the OM latch is not used. P.S. Pay attention to BHT. Why is it so big, if we only read 10 records?
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