What are you waiting for?

Report
What are you waiting for?
A reason for waiting around.
Richard Banville
Fellow, Progress Software
June 7, 2011
Playing Fair and Being Consistent
 Why do I need to wait?
• Shared resource synchronization
 Implementation restrictions
• Wait on only one resource
• Concurrent waits
– Timer interrupt (timeout processing)
– Screen/process interrupt
– Network
“table1 in use by user1 on p/97. Wait or press CTRL-C to stop.”
 Focus is on resource waits
• How & why we wait
2
© 2011 Progress Software Corporation. All rights reserved.
What can a user wait on
Some you can avoid; Some are out of your control.
• Undo/rollback
 Database Resource
• Internal resource
– Shared data structure
 Schema changes (some)
– Buffer lock
 Quiet point
– TXE lock
 Maintenance activity
• Checkpoint
• BI/AI (buffer, I/O…)
• Transaction end
– Unique key insertion
• Record lock
• Database extends
• Backup
• Table/index move/activate
 Replication (pica)
 Screen input (select)
 Network message (poll)
• Page writers
 System calls
• Index operation
 I/O (low level)
– Search, split
3
• Login (semaphore)
© 2011 Progress Software Corporation. All rights reserved.
 Etc.
Wait Mechanisms
 Latches
• Used for “short term” waits
• Waiting user NOT visible (activity & waits are visible)
• Test, test-and-set (atomically), “nap”, try again
 Semaphores
• Used for “long term” waits
• Waiting user visible via promon (VSTs)
• Often can be controlled at application level
– Example: record lock duration
• Sometimes not
– Example: I/O duration
• Try, queue, wait for explicit wakeup
4
© 2011 Progress Software Corporation. All rights reserved.
Semaphores
5
© 2011 Progress Software Corporation. All rights reserved.
Semaphores
 Wait on semaphore summary
• “Long term” wait synchronization mechanism
• Always server side
• Unix semaphore info:
– ipcs -sa
– -semsets: min 1, max 32,000, default 3
– Kernel control
o SEMMNS - max semaphores available system wide
o SEMMNI - max semaphore sets
o SEMMSL - max semaphores per set
• Semaphore usage
– Ready semaphore – db startup
– Login semaphore – connect/disconnect
– Resource wait semaphore – one per connection
6
© 2011 Progress Software Corporation. All rights reserved.
Semaphores
-semsets (3)
#1
#2
26 Connection sems = -n 20 + -Mn 4 + 1 (broker) + 1 (proshut)
Ready
Login
5 spares
User1
User3
User5
…
• What could I be waiting on?
– Ready/Login semaphore
– Schema lock wait
– Record lock wait
– Buffer lock wait (db, ai, bi)
• Ordered wait/wake-up (fifo queue)
– Add to queue
– Decrement semaphore
#3
– OS suspend state
User2
User4
User6
…
– When resource available, semaphore “ping’ed”
– OS activates process again
• High semaphore waits
– Application contention
– Buffer contention
7
© 2011 Progress Software Corporation. All rights reserved.
Promon R&D: Other Display
12/07/10
Activity: Other
Wait on semaphore
Total
1545
Per Min
1862
Per Sec
31.00
Per Tx
0.21
 Wait on semaphore summary
• High waits can indicate a potential for improvement
– Increase resources
– Alter application
o Improve queries
o Avoid full table scans
o Alter lock behavior
– Physical changes (Use TII storage areas)
• Direct connections only
• Zero and monitor
• Contrast with a more happy time
8
© 2011 Progress Software Corporation. All rights reserved.
Performance Indicators (summary)
12/07/10
Activity: Performance Indicators
Total waits
Lock waits
Resource waits
Latch timeouts
Total
1558
337
1221
1625
Per Min
1870
404
1465
1950
Per Sec
31.16
6.74
24.42
32.50
Per Tx
0.23
0.05
0.18
0.24
• Total waits – Lock waits + Resource waits
• Lock waits (application)
– Record lock
– Schema lock
– Transaction end
(unique key insertion)
• Latch timeouts
– #times –spin exhausted
9
© 2011 Progress Software Corporation. All rights reserved.
• Resource waits (internal)
– Row get lock
– Buffered lock in shared
memory (db, ai, bi)
– Buffer I/O (db, ai, bi)
– Micro-transaction end lock
– Latches (queue latches)
Promon: Other Display vs Performance Indicators
12/07/10
Activity: Other
Wait on semaphore
12/07/10
Total
1545
Per Min
1862
Per Sec
31.00
Per Tx
0.21
Activity: Performance Indicators
Total waits
Lock waits
Resource waits
Total
1558
337
1221
Per Min
1870
404
1465
Per Sec
31.16
6.74
24.42
Per Tx
0.23
0.05
0.18
 Semaphore waits != Total waits
– Race condition – stats not (always) latched
– Client server record waits – no semaphore wait
– Semaphore latch waits – no lock/resource wait
– “DB Intent” waits counted twice – excl buffer wait
10
© 2011 Progress Software Corporation. All rights reserved.
Promon: Other Display vs Performance Indicators
12/07/10
Activity: Other
Total
Wait on semaphore
1545
14
* Non-blocking waits
1
* Semaphore latch waits
12/07/10
Per Sec
31.00
0.16
0.00
Per Tx
0.21
0.02
0.00
Activity: Performance Indicators
Total waits
Lock waits
Resource waits
11
Per Min
1862
8
0
Total
1558
337
1221
© 2011 Progress Software Corporation. All rights reserved.
Per Min Per Sec
1870
31.16
404
6.74
1465
24.42
Per Tx
0.23
0.05
0.18
Wait Identification
12
© 2011 Progress Software Corporation. All rights reserved.
Locks vs Locks Waits
12/07/10
Usr
0
5
6
User
Name
richb
richb
richb
Other: Performance Indicators:
Lock Requests By User
--- Record --- ---- Trans --- --- Schema --Locks Waits Locks Waits Locks Waits
0
0
0
0
0
0
12
0
1
0
0
0
222
10
10
0
0
0
 Locks from “Performance Indicators” option
• Broken out by user
• Can indicate a performance issue
• Record locks/waits
• Transaction locks/waits
• Schema locks/waits
13
© 2011 Progress Software Corporation. All rights reserved.
Recovery Waits
12/07/10
Activity: BI Log
Total
Busy buffer waits
10
Empty buffer waits
1
Log force waits
0
Per Min
2
0
0
Per Sec
0.02
0.00
0.00
Per Tx
0.20
0.00
0.00
• Busy buffer waits
– # of waits for exclusive BI buffer access
– Wait for other user to finish BI buffer update/write
– Only seen with page writers (due to MTX latch)
• Empty buffer waits
– # of waits because all buffers were full
– Increase –bibufs and run with biw
• Log force waits
– # of waits for “commit notes” to be written to disk
– Obsolete
14
© 2011 Progress Software Corporation. All rights reserved.
BI Buffer Pool – Recording a change
Forward Processing -bibufs 10
Free List
free - a
Current
Output Buffer
Modified
Queue
32
31
free - b
free - c
30
New
Notes
(Actions)
29
free - d
free - e
15
© 2011 Progress Software Corporation. All rights reserved.
BI
PROMON:
Total BI Writes
Records (notes) written
Partial Writes
- Busy buffer waits
- increase bibufs
- Empty buffer waits
- increase bibufs
- biw, apw
Label Confusion
12/07/10
Usr Name
7
richb
8
richb
12/07/10
Usr Name
7
richb
8
richb
Status: Blocked Clients
Type
SELF/ABL
SELF/ABL
Wait Trans id
TRAN
2053
REC
32768
2104
2224
R&D
Blocked
Clients
Status: Blocked Clients
Type
SELF/ABL
SELF/ABL
Wait Wait Info Trans id
TRAN
2053
2104
REC
32768
2224
Current trid
Not blocking trid
User Control:
-- Wait Info -Usr Name Type
Wait
Table Dbkey Trans
0 dba
BROK
-0
0
0
1 dba
SERV
-0
0
0
6 bob
SELF/ABL REC
2
385
2108
24 joe
REMC/ABL TRAN
0
2053
2261
16
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Display
Users
Blocked Clients: Record Lock
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL
REC
1282
2104
 REC – Waiting on a record lock
• “Record Lock” (Activity lock description)
• Wait info: Record’s rowid
• No table information
• Record lock wait in Lock Table option has more detail
– Including table information
• Easy to identify if “hung”
18
© 2011 Progress Software Corporation. All rights reserved.
Record Lock Waits
12/07/10
Status: Lock Table
Usr Name Trans ID
6 richb 121759
7 richb 121761
Type
REC
REC
Rowid
Rec-id Table
8199
2
8199
2
 Flags: Lock request
Flags
X
S QH
Tran State
Begin
Dead
(Table only)
• S – Shared
• X – Exclusive
• SX – Shared/Exclusive(?)
• IS – Intent shared
• IX – intent exclusive
• SIX – SHR w/intent EXCL
 Flags: Lock state
• U – Upgrade, L - Limbo, Q - Queued, P - Purge, H – No Hold
 Tran State
• Dead, Begin, Active, Prep, Phase 1, Phase 2
 Record lock queuing mechanism
X
19
SQ
SQ
© 2011 Progress Software Corporation. All rights reserved.
XQ
S
S
XQ
SQ
Locking Code Examples
find first customer.
pause message "about to assign".
assign name = "xxx“.
S
X
find last customer.
assign cust-num = 39999.
release customer.
pause.
S
find first customer exclusive-lock.
delete customer.
X
UQ
X
X
IX
Deadlock Alert
(on conflict)
(no conflict)
Limbo record lock
L
Record lock (‘til purged)
L
P
Limbo Table lock
Purge lock until
released internally
pause message “deleted!”.
NOTE: Record locks released
Limbo table lock: Serialization Isolation Cooperation
(since record lock(s) released)
20
© 2011 Progress Software Corporation. All rights reserved.
Lock Waits Statistics
12/07/10
Activity: Lock Table
Total
Per Min
Per Sec
Per Tx
Waits:
Share
59
*Intent Share
0
Exclusive
218
*Intent Exclusive
0
*Share Intent Excl 0
Upgrade
0
Record Get Lock 0
2
0
9
0
0
0
0
0.04
0.00
0.15
0.00
0.00
0.00
0.00
0.01
0.00
0.04
0.00
0.00
0.00
0.00
0
11
0.00
0.19
0.00
0.05
Table Lock
Record Lock
0
277
 Nice overall wait summary
• Helps identify application performance issues
 *Table locks only
21
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Record Get
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL
RGET
1282
2104
 RGET – Record “get lock”
• "Record Get Lock"
• Wait info: Record’s rowid
• No-lock wait
User 6
1.
Modify/delete record
( buffer state change)
•
•
22
User 7
2.
3.
No-lock read a record Frag1
Read record fragment #2
Must wait for user6 shm buffer update to get consistent record.
New optimistic locking – only needed for fragmented records.
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Buffer Locks
12/07/10
Usr Name
7
richb
8
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL BKSH
1280
2104
SELF/ABL BKEX
192
2234
 BKSH & BKEX – Database buffer locks
• Wait info: Block identifier (dbkey) of block
• Area information would be useful
• “DB Buf S Lock” - OR – “DB Buf X Lock”
• 12 (BKS2), 13 (BKX2)  “DB Buf S/X Lock LRU2”
– Alternate buffer pool lock
 Catch all (sequence(192), object block, etc)
 Record updates:
• Record lock first, then buffer lock
 “Rarely” lock multiple buffers – deadlock avoidance
23
© 2011 Progress Software Corporation. All rights reserved.
Record Locator (indicator, block #, row #)
Rowid Consists of 3 parts (32 bit example)
Block number: 1 to whatever
Row #: 0 to 255 (based
on RPB)
00 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Looking for ROWID 42562, Table 1, Area 7 w/64 RPB setting
Block # (in area): 665
Row #: 2
Block identifier (dbkey): 42560
Rowid: 42562
(Row # as zeros)
(Row # included)
00 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 1 1 0 0 1 00 00 00 00 10
1 00
Block number: 1 to 2^25
24
© 2011 Progress Software Corporation. All rights reserved.
Row #: 0 to 63
Online Backup Wait
Online “point in time” backup - can result in BKEX waits
25
© 2011 Progress Software Corporation. All rights reserved.
Online Backup Wait
Online “point in time” backup - can result in BKEX waits
Area 6
Area 7
Area 8
…
BI
Modify request
Modify request
Online Backup
User 1
Wait…
BFP
BKEX
Backup
queue
MTX
TXE
BFP
Back it up and mark it
•
•
26
Wait on (TXE) semaphore during bi backup
Wait on BKEX during data backup
© 2011 Progress Software Corporation. All rights reserved.
.bak
Blocked Clients: Read/Write I/O
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL DBRD
1280
2104
 DBRD & DBWR – Database read/write
• “DB Buf Read” – OR – “DB Buf Write”
• Wait info: Block identifier
 DBW2 (14)
• Same as DBWR but for alternate buffer pool
 BIRD, BIWR, AIRD, AIWR – Bi/Ai read/write
• “BI Buf Read” –OR – “BI Buf Write”
• Wait info: bi/ai block # (not particularly useful to you)
• Can use to determine if waiting on different block (not hung)
27
© 2011 Progress Software Corporation. All rights reserved.
Buffer Pool Access
BKSH & BKEX vs DBRD & DBWR
Flush/overwrite for paging
Updating different records in same block
User3
Record read/update
User1
User2
BK Buffer
lock
Block in
memory
DB Buffer
lock
DB
APW
DBRD – reading in – all must wait!
Flush for performance
DBWR – Writing out, cannot be changed
BKSH – In memory, read attempt
BKEX – In memory, change attempt
•
28
Pretty much same mechanism for all buffer pools (-B, -B2, -bibuf, -aibuf)
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Special Buffer Lock
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL DBSI
1280
2104
 DBSI – Intent to update buffer lock
• “DB Buf I Lock”
• Wait info: Block identifier (dbkey) of conflict
• Used by index manager when deleting or inserting entries
• “Safe” locking protocol
29
© 2011 Progress Software Corporation. All rights reserved.
Insert an Index Key Entry
- Shared
root
Block’s DBKEY
Type
Next DBKEY in Chain
Top
Bot
Num
Entries
Chain
– DBSI buffer lock
– “crabbing” mechanism
– Release previous node
– Increases concurrency
Backup Ctr
Block Update Counter
Index
Reserved
No.
Bytes
Dummy Entry . . .
Used
. . . Compressed Index Entries . . .
ooo
. . . Compressed Index Entries . . .
Free Space
- Shared
-DBSI internal
(on split)
Block’s DBKEY
Type Chain Backup Ctr
Block’s DBKEY
Type Chain Backup Ctr
Next DBKEY in Chain
Block Update Counter
Block’s DBKEY
Type Chain Backup Ctr
Next DBKEY in Chain
Block Update Counter
Top
Bot
Index
Reserved
Next DBKEY in Chain
Block Update Counter
Top
Bot
Index
Reserved No.
Num
Bytes
Dummy Entry . . .
No.
Top
Bot
Index
Reserved
Num
Bytes
Dummy EntryUsed
...
Entries
No.
. . . Compressed Index Entries . . .
EntriesEntry . . . Used
Num
Bytes
Dummy
. . . Compressed Index Entries . . .
Entries
Used
. . . Compressed Index Entries . . .
ooo
ooo
ooo
. . . Compressed Index Entries . . .
. . . Compressed Index Entries . . .
. . . Compressed Index Entries . . .
Free Space
Free Space
Free Space
- DBSI
records
30
Type
Top
Bot
Num
Entries
Chain
Backup Ctr
Block Update Counter
Index
Reserved
No.
Bytes
Dummy Entry . . .
Used
. . . Compressed Index Entries . . .
ooo
. . . Compressed Index Entries . . .
Free Space
Block’s DBKEY
Type Chain Backup Ctr
Block’s DBKEY
Type Chain Backup Ctr
Next DBKEY in Chain
Block Update Counter
Type Chain Backup Ctr
Block’s DBKEY
Type Chain
Next DBKEY in Chain
Block Update Counter
Top
Bot
Index
Reserved
Block’s DBKEY
Type Chain Backup Ctr
Next DBKEY in Chain
Block Update Counter
Next DBKEY in Chain
Block Update Counter
Top
Bot
Index
Reserved No.
Block’s DBKEY
Type Chain Backup Ctr
Num
Bytes
Dummy
Entry . . .
Next
DBKEY
in
Chain
Block
Update
Counter
Top
Bot
Index
Reserved
No.
Block’s DBKEY
Type Chain Backup Ctr
Top
Bot
Index
Reserved
Entries
Used
Num
Bytes
Dummy Entry
...
No.
Next DBKEY in Chain
Block Update Counter
. . . Compressed Index Entries . . .
Top
Bot
Index
Reserved No.
Num
Bytes
Dummy Entry
...
Entries
Used
Next DBKEY in Chain
Block Update Counter
Num
Bytes
Dummy Entry . . .
. . . Compressed Index Entries . . .
Entries
Used
Top
Bot
Index
Reserved No.
Entries
Used
Num
Bytes
Dummy Entry
...
. . . Compressed Index Entries . . .
Top
Bot
Index
Reserved
No.
. . . Compressed Index Entries . . .
Entries
Used
Num
Bytes
Dummy
Entry
.
.
.
ooo
No.
. . . Compressed Index Entries . . .
Num
Bytes Entries
Dummy
Used Entry . . .
ooo
. . . Compressed Index Entries . . .
Entries
Used
ooo
ooo
. . . Compressed Index Entries . . .
. . . Compressed Index Entries . . .
ooo
. . . Compressed Index Entries . . .
ooo
. . . Compressed Index Entries . . .
Free Space
. . . Compressed Index Entries . . .
ooo
Free Space
. . . Compressed Index Entries . . .
Free Space
Free Space
. . . Compressed Index Entries . . .
Free Space
. . . Compressed Index Entries . . .
Free Space
Free Space
Block’s DBKEY
Backup Ctr
leaf
Block’s DBKEY
Next DBKEY in Chain
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Buffer Availability
12/07/10
Usr
Name
Status: Blocked Clients
Type
Wait Wait Info Trans id
 NOBF (11) – Wait for available buffer in -B
• Wait statistic accumulated
• Actual wait never seen in “Blocked Client”
• Wait info: None
• Shows up as “DB Buf Avail” in resource waits
• Wait mechanism
– Sleep for a second, then retry
– 5 attempts then hard failure
– Error message: “Not enough database buffers (-B)”
31
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Transaction End
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL TRAN
2053
2104
Wait info is actually a trid
 TRAN – Wait for transaction to commit
• “Trans Commit"
• Wait info: transaction Id waiting on
• Can occur when adding a unique index key entry
User 6
User 7
1. Begin transaction
3. Begin transaction
2. Delete unique key [email protected]
(or insert)
4. Insert unique key [email protected]
Must wait for user6 to commit or rollback.
32
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Micro-transaction
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL
TXE
1
2104
 TXE - Micro-transaction wait
• A micro-transaction?
• Wait info:
– 1: Share – buffer read/write
– 2: Update – multi-buffer change
– 3: Commit – commit note & txn table sync
– 4: Exclusive – Quiet point and backup
• No commit TXE if multi-buffer update already outstanding
33
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Schema Lock
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL
SCH
10
2104
 SCH – Schema lock
• “Schema Lock"
• Values
– 9 - Share lock request
– 10 - Exclusive lock request
User 6
User 7
1.
Login – cache schema
3.
Change Schema (w/o online)
2.
Share schema lock
4.
Exclusive schema lock
“Database in use by richb on pts/274. Wait or press CTRL-C to stop.”
34
© 2011 Progress Software Corporation. All rights reserved.
Blocked Clients: Miscellaneous
12/07/10
Status: Blocked Clients
Usr
Name Type
Wait Wait Info Trans id
7
richb
SELF/ABL SRPL
0
2104
 SRPL – OpenEdge Site Replication
•
"Repl TEND Ack“
•
Waiting for TEND ACK from a Sync Repl Agent
•
Schema lock request
•
Wait info: none.
 DBSQ – Service Queue
•
"DBSQ Send Lock“
•
Database service queue message wait. User waiting to queue IPC
message to database service queue
•
Wait info: none.
 STCA – Statement Cache
35
•
Statement caching wait
•
Wait info: none.
© 2011 Progress Software Corporation. All rights reserved.
Other Major Waits
36
© 2011 Progress Software Corporation. All rights reserved.
Other Major Waits: Checkpoint
12/07/10
Other: Checkpoints
Ckpt
------ Database Writes -----No. Time
Len Freq Dirty CPT Q Scan APW Q Flushes
2 09:34:57 317
0
170
0
0
0
0
1 09:14:19 1238 1238
272
0
0
0
72
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL TXE
3
2104
 Checkpoint – sync in memory changes
• TXE – lock
– Prevents transaction commit
• MTX – latch
– Prevents db changes
• BIB – latch
– Prevents BIW writes
• Wait not definitive; Latch waits not shown in “Blocked Clients”
37
© 2011 Progress Software Corporation. All rights reserved.
Other Major Waits: Quietpoint
12/07/10
Usr Name
7
richb
Status: Blocked Clients
Type
Wait Wait Info Trans id
SELF/ABL
TXE
1
2104
 Quietpoint
• Many wait examples – shared TXE share wait shown above
• .lg file – “Quiet point has been enabled by the broker”
• TXE – exclusive lock
– Prevents data access
• MTX – latch
– Prevents db changes
• BIB/AIB – latch
– Prevents BIW/AIW writes
38
© 2011 Progress Software Corporation. All rights reserved.
Summary
 Many different waits conditions
 Identifying waits
• Help id performance bottlenecks
 Understanding wait conditions
• Help remove performance bottlenecks
39
© 2011 Progress Software Corporation. All rights reserved.
?
Questions
40
© 2011 Progress Software Corporation. All rights reserved.
41
© 2011 Progress Software Corporation. All rights reserved.
Sept. 19 – 22, 2011
Boston Westin Waterfront Hotel
and Boston Convention & Exhibition Center
Table Lock Types
43
Lock Type
Allow
Block
Intent Share (IS)
Row S
Table X
Intent Exclusive (IX)
Row X
Table X
Shared (S)
Row S
Row X
Shared with Intent
Exclusive (SIX)
Row S, X
other Row X
Exclusive (X)
Row S, X
any other access
© 2011 Progress Software Corporation. All rights reserved.
Table Lock Compatibility
Lock Request Type
Other Active Locks
44
IS
IX
S
SIX
X
None
OK
OK
OK
OK
OK
IS
OK
OK
OK
-Q-
-Q-
IX
OK
OK
-Q-
-Q-
-Q-
S
OK
-Q-
OK
-Q-
-Q-
SIX
OK
-Q-
-Q-
-Q-
-Q-
X
-Q-
-Q-
-Q-
-Q-
-Q-
© 2011 Progress Software Corporation. All rights reserved.
Progress Implementation
Isolation
Level
Read
Uncommitted
Read
Committed
Repeatable
Read
Serializable
45
Select
Table
Record
Lock
Lock
None
Intent
Share
Intent
Share
Share
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None
Insert/Update
Table
Record
Lock
Lock
Not
Allowed
Not
Allowed
Share
Intent
Exclusive
Exclusive
Share
Intent
Exclusive
Exclusive
None
Share
Intent
Exclusive
Exclusive

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