Informix chat with the lab

1. Informix Chat with the Lab
August 16, 2006
Stuart Litel, President, International Informix Users Group
Jerry Keesee, Director of the Informix Lab
John F. Miller III, Senior Technical Staff Member

2.  Educational Seminars
 Hands on with Advanced features
of IDS 10
 Using Perl, DBI and CGI with
Databases
 Technical Presentations
 Database Performance
 Disaster Recovery and Data
Availability
 Application Development
 Security
 Examples and Solutions
 IDS Internals
 Informix support
 Keynote Presentation – “Information as a Service... A New Era in Databases”
Bob Picciano, VP of IBM Database Services, Information Management Division
 Where do our speakers come
from?
 IBM US
 IBM UK
 IBM DE
 IBM CZ
 Informix users
 Products & Services Exhibitions
For conference information and
registration, go to www.iiug.org/conf
* Note: All registration is
handled by IDUG – The
International DB2 User
Group (IDUG).

3. Announcing IIUG / IDUG North America 2007
May 6 – 10, San Jose California
• Call for presentations is now under way! This is YOUR opportunity to share
your Informix experience and expertise with an audience of your peers.
• FREE conference registration if your presentation is selected.
• Single session (60 minutes) or Double (120 minutes)
• Abstract deadline is September 1st, 2006 – so start working on it now!
• All that is needed for abstract submission is Title, Brief description of the
session and an outline.
• Entire presentation is not due for a few months after being selected. Over
50 Informix sessions to be presented by fellow Informix users like yourself.
• Go to the IIUG Website for more information and a link to the Call for
Presentations – http://www.iiug.org/conf/
• See you in San Jose…. The Heart of Silicon Valley.

4. Overview
• Recent Changes to onstat
• View I/O through onstat
– Disk IO
– Network IO
• Memory Usage
• Cache Sizes
• View Action by
– User
– Table

5. Recent onstat changes
• onstat –m
– Displays the message file when the server is
offline
• onstat –c
– Displays the configuration file when the server is
offline

6. New onstat Options
• onstat –g env User/System
environment
• onstat –g stm Statement memory
usage
• onstat –g rwm Read/Write Mutex
• onstat –C Btree Scanner
• onstat –g cac Display various
caches

7. Looking at Environment
onstat –g env [sid]
cmd> onstat -g env
Server start-up environment:
Variable Value [values-list]
DBDELIMITER |
DBPATH .
DBTEMP /tmp
cmd> onstat -g env 147
Environment for session 147:
Variable Value [values-list]
CLIENT_LOCALE en_US.8859-1
DBDELIMITER |
DBPATH //jmiller_94
DBTEMP /usr/tmp
Session Environment
Server Environment

8. Memory by SQL Statement
onstat –g stm
• Shows all currently active SQL statements
• Shows the amount of memory each SQL
statement currently using in bytes
command> onstat -g stm
session 16 --------------------------------------
sdblock heapsz statement ('*' = Open cursor)
bca2018 11936 *select * from customer, orders
session 14 ---------------------------------------
sdblock heapsz statement ('*' = Open cursor)
bc4d018 2048 Database 'insdel'
bc4d140 8496 select count(*) from informix.systables;
bc4d268 6264 *select * from t2

9. Watching The Inverted Pyramid
onstat –g iov
AIO I/O vps:
class/vp s io/s totalops dskread dskwrite dskcopy wakeups io/wup errors
msc 0 i 0.0 26 0 0 0 26 1.0 0
aio 0 s 0.2 1080 883 188 0 849 1.3 0
aio 1 i 0.2 1072 874 189 0 830 1.3 0
aio 2 s 0.2 884 852 28 0 699 1.3 0
aio 3 i 0.2 647 831 13 0 769 1.1 0
aio 4 i 0.2 252 832 16 0 712 1.2 0
aio 5 i 0.2 24 811 12 0 673 1.2 0
pio 0 i 0.0 2 0 2 0 3 0.7 0
lio 0 i 0.0 3 0 3 0 4 0.8 0

10. Errors indicate a lack of resources in the I/O subsystem
Especially important if using KAIO
Watching The Inverted Pyramid
onstat –g iov
AIO I/O vps:
class/vp s io/s totalops dskread dskwrite dskcopy wakeups io/wup errors
msc 0 i 0.0 26 0 0 0 26 1.0 0
aio 0 s 0.2 1080 883 188 0 849 1.3 0
aio 1 i 0.2 1072 874 189 0 830 1.3 0
aio 2 s 0.2 884 852 28 0 699 1.3 0
aio 3 i 0.2 647 831 13 0 769 1.1 0
aio 4 i 0.2 252 832 16 0 712 1.2 0
aio 5 i 0.2 24 811 12 0 673 1.2 0
pio 0 i 0.0 2 0 2 0 3 0.7 0
lio 0 i 0.0 3 0 3 0 4 0.8 0

11. S indicates in System call (VP is currently busy)
I indicates the VP is currently idle
Watching The Inverted Pyramid
onstat –g iov
AIO I/O vps:
class/vp s io/s totalops dskread dskwrite dskcopy wakeups io/wup errors
msc 0 i 0.0 26 0 0 0 26 1.0 0
aio 0 s 0.2 1080 883 188 0 849 1.3 0
aio 1 i 0.2 1072 874 189 0 830 1.3 0
aio 2 s 0.2 884 852 28 0 699 1.3 0
aio 3 i 0.2 647 831 13 0 769 1.1 0
aio 4 i 0.2 252 832 16 0 712 1.2 0
aio 5 i 0.2 24 811 12 0 673 1.2 0
pio 0 i 0.0 2 0 2 0 3 0.7 0
lio 0 i 0.0 3 0 3 0 4 0.8 0

12. Monitoring I/O Resources by File
onstat -g iof
AIO global files:
gfd pathname totalops dskread dskwrite io/s
3 /dev/tsinfo1 1506 1393 113 0.0
4 /dev/tsinfo2 776 3 773 0.0
5 /dev/tsinfo0 22205 7994 14211 0.4
6 /dev/tsinfo3 55092 54102 990 1.1
dskread/dskwrite
Number of read/write system calls
io/s
Average I/O operations per second

13. Network Resources By Client Type
onstat -g ntd
Client Type Calls Accepted Rejected Read Write
sqlexec yes 4744 26 3911350 3882491
srvinfx yes 92 0 0 0
oncheck yes 410 0 114668 114851
onmonitor yes 4 0 136 137
ontape yes 5 0 66113 66117
Client Type
The type of client connecting to the IDS
Accepted/Rejected
Number of times a successful/unsuccessful connection occurred
Read/Write
The number of times the engine received/sent data to the clients

14. Network Resources By User
onstat -g ntu
Individual thread network information (basic):
netscb type thread name sid fd poll reads writes q-nrm q-exp
3fc97bc soctcp sqlexec 5269 66 5 38 38 0/ 1 0/ 0
3f857bc soctcp sqlexec 5268 64 5 1 1 0/ 1 0/ 0
3fa97bc soctcp sqlexec 5267 62 5 41 41 0/ 1 0/ 0
3e737bc soctcp sqlexec 5264 52 5 1586 1585 0/ 1 0/ 0
3c7f7bc soctcp sqlexec 5262 29 5 357 357 0/ 1 0/ 0
sid
User session id
type
Indicates the communication protocol used for this thread
reads/writes
The number of OnLine packets received/sent by the OnLine

15. Show System Memory Usage
onstat –g seg
• Shows the amount of memory current
allocate, used and free
• Block of memory are in 4KB units
Segment Summary:
id key addr size ovhd class blkused blkfree
93001 1386432513 10a000000 13631488 424320 R 3160 168
93002 1386432514 10ad00000 31457280 1696 V 4685 2995
9509 1386432519 10eb00000 8388608 992 V 123 1925
Total: - - 53477376 - - 7968 5088

16. Useful onstat Options
• onstat –P Buffers by Table
• onstat –g tpf Actions by Thread
• onstat –g ppf Actions by Table

17. Monitoring Different Caches
• Buffer Cache
– Stores commonly accessed data/index pages from
disk
• Data Dictionary
– Cache used to store commonly accessed system
catalog information
• Data Distributions
– Cache to store update statistics medium/high data
used by the optimizer to build query plans
• Stored Procedure Cache
– Caches stored procedure code
• Extensible Caches

18. Buffer Cache Sizing (onstat –p)
• System Read Cache
– Increasing buffers improves read cache rate
– 90% or better is a good read cache
• System Write Cache
– Increasing buffers may not help the write cache
– LRU parameters and CKPTINTVL greatly affect the
write cache
Profile
dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached
78201 141506 1538858 94.92 14480 23668 298884 95.16

19. • Partnum
– Numeric link to
objects name
table/index/fragment
• Total
– Number of pages
currently buffered for
this table/fragment
• Data
– Number of data
page currently
buffered for this
table/fragment
Buffer Pool Stats by Table
onstat –P
partnum total btree data other dirty
1048707 10 6 2 2 0
1048710 4 1 1 2 0
1048714 3 1 1 1 0
1049081 257 0 255 2 0
1049472 5462 0 5459 3 4635
Totals: 9000 52 5747 3201 4636
Percentages:
Data 72.86
Btree 25.58
Other 01.57

20. Buffer Pool Stats by Table
onstat –P
partnum total btree data other dirty
1048707 10 6 2 2 0
1048710 4 1 1 2 0
1048714 3 1 1 1 0
1049081 257 0 255 2 0
1049472 5462 0 5459 3 4635
Totals: 9000 52 5747 3201 4636
Percentages:
Data 72.86
Btree 25.58
Other 01.57
Buffer Pool System Statistics
• Data
– Percentage of the
buffer pool holding
data pages
• Btree
– Percentage of the
buffer pool holding
index pages
• Other
– Control pages, such
as, reserve pages,
bitmap
Ensure the ratio of System Data/Btree
pages looks reasonable for your
workload

21. Data Dictionary Cache
onstat -g dic
• Shows the tables in the data dictionary
• Total number of current entries
– Currently 2
• Total number of available cache locations
– Currently 31 * 10 = 310
Dictionary Cache: Number of lists: 31, Maximum list size: 10
list# size refcnt dirty? heapptr table name
--------------------------------------------------------
11 1 1 no a2ecf88 d1@olympia:jmiller.t2
25 1 0 no a2ec330 d1@olympia:informix.systables
Total number of dictionary entries: 2

22. Data Distributions Cache
onstat –g dsc
Distribution Cache:
Number of lists : 31
PC_POOLSIZE : 50
Number of entries : 2
Number of entries in use : 0
Distribution Cache Entries:
list# id ref_cnt dropped? heap_ptr distribution name
-----------------------------------------------------------------
15 0 0 0 abe2c20 stores@oly:customer.lname
7 0 0 0 abe3820 stores@oly:customer.company
Total number of distribution entries: 2.
Cache used to store update statistics
medium or high information

23. Stored Procedure Cache
onstat –g prc
Stored Procedure Cache:
Number of lists : 31
PC_POOLSIZE : 50
Number of entries : 3
Number of inuse entries : 0
Stored Procedure Cache Entries:
list# id ref_cnt dropped? heap_ptr procedure name
--------------------------------------------------------------
4 1 0 0 abe3c20 stores7@olympia:informix.systdist
22 2 0 0 a2f0c58 sysmaster@olympia:informix.bitval
14 3 0 0 a2f0458 sysmaster@olympia:informix.l2date
Total number of procedure entries: 3.

24. Extensible Caches
• User Defined Routines
• Routine Cache
• Type Cache
• Cast Cache
• OpClass
• Access Method Cache
• Secondary Access Method Cache
• User Defined Aggregate Cache

25. Partition profiles
partnum lkrqs lkwts dlks touts isrd iswrt isrwt isdel bfrd bfwrt seqsc
9437341 11 0 0 0 0 4 0 0 26 14 0
9437394 205 0 0 0 63 11 0 8 318 129 6
10485999 15 0 0 0 0 6 0 0 29 18 0
11534359 5 0 0 0 0 1 0 0 18 8 0
6291561 0 0 0 0 1854 0 0 0 3605 0 103
Actions by Table
onstat -g ppf
Table Locks SQL like Actions Buffers

26. Partition profiles
partnum lkrqs lkwts dlks touts isrd iswrt isrwt isdel bfrd bfwrt seqsc
9437341 11 0 0 0 0 4 0 0 26 14 0
9437394 205 0 0 0 63 11 0 8 318 129 6
10485999 15 0 0 0 0 6 0 0 29 18 0
11534359 5 0 0 0 0 1 0 0 18 8 0
6291561 0 0 0 0 1854 0 0 0 3605 0 103
Actions by Table
onstat -g ppf
• partnum
Decimal number linked to systables:partnum
• lkrqs LocK ReQuestS
Number of times a lock has been acquired on the table
• lkwts LocK WaiTS
Number of times a user had to wait when acquiring a lock on this table
• Dlks DeadLocKS

27. Partition profiles
partnum lkrqs lkwts dlks touts isrd iswrt isrwt isdel bfrd bfwrt seqsc
9437341 11 0 0 0 0 4 0 0 26 14 0
9437394 205 0 0 0 63 11 0 8 318 129 6
10485999 15 0 0 0 0 6 0 0 29 18 0
11534359 5 0 0 0 0 1 0 0 18 8 0
6291561 0 0 0 0 1854 0 0 0 3605 0 103
Actions by Table
onstat -g ppf
• isrd ISam Reads
Number of times a rows has been read from this table
• iswrt ISam WriTes
Number of calls to insert a row into this table
• isrwt ISam ReWriTes
Number of calls to update a row in this table
• Isdel ISam DELetes
Number of calls to delete a row from this table

28. Partition profiles
partnum lkrqs lkwts dlks touts isrd iswrt isrwt isdel bfrd bfwrt seqsc
9437341 11 0 0 0 0 4 0 0 26 14 0
9437394 205 0 0 0 63 11 0 8 318 129 6
10485999 15 0 0 0 0 6 0 0 29 18 0
11534359 5 0 0 0 0 1 0 0 18 8 0
6291561 0 0 0 0 1854 0 0 0 3605 0 103
Actions by Table
onstat -g ppf
• bfrd BuFfer ReaDs
Number of individual page reads from this table
• bfwrt BuFfer WRites
Number of times a page in this table has been modified
• seqsc SeQuential SCans
Number of sequential table scans

29. Actions by User/Thread
onstat -g tpf
• User Thread
• Locks
• Log Records
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10
• SQL Like Actions
• Transactions
• Buffers

30. Actions by User/Thread
onstat -g tpf
• tid Thread ID
– Each user can have one or more threads, the TID has
a many-to-one relationship to the user's Session ID
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10

31. Actions by User/Thread
onstat -g tpf
• lgrs LoG Records
The number of log records created by this thread
• lsus Log Space Used
The number of bytes of logical log space used by this thread
• lsmx Log Space Maximum
– The space used by the thread's largest transaction
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10

32. Actions by User/Thread
onstat -g tpf
• isct ISam CommiT
The number of commits
• isrb ISam RollBack
The number of times this thread has rolled back a
transaction
• lx Long Transactions
The number of long transactions perpetrated by this thread
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10

33. Actions by User/Thread
onstat -g tpf
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10
• isrd ISam Reads
Number of times a row has been read by this thread
• Iswr ISam WRites
Number of calls to insert a row by this thread
• Isrw ISam ReWrites
Number of calls to update a row by this thread
• Isdl ISam DeLetes
Number of calls to delete a row by this thread

34. • lkreqs LocK REQuestS
Number of times a lock has been acquired by this thread
• lkwts LocK WaiTS
Number of times a user had to wait when acquiring a lock
• dlksDeadLocKS
Number of Deadlock errors encountered by this user
• to lock TimeOuts
Number of times a user waited on a lock, but failed to acquire
the lock in the time allotted
Actions by User/Thread
onstat -g tpf
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10

35. Actions by User/Thread
onstat -g tpf
tid lkreqs lkw dl to lgrs isrd iswr isrw isdl isct isrb lx bfr bfw lsus lsmx seq
42 35 0 0 0 408 0 0 0 0 11 0 0 207 128 856 120 0
48 35110 0 0 0 32 0 0 0 0 14 0 0 638 2294 0 208 0
3873 4646 0 0 0 0 1469 89 0 0 0 0 0 6683 1080 0 0 2
3876 498 0 0 0 0 93 25 0 2 0 0 0 535 200 0 0 16
3648 1946 0 0 0 68 6266 42 4 1 5 0 0 4238 495 0 4488 10
• Monitor the ratio of all SQL like actions over buffer actions.
This gives an indication of how much work is done for each
row processed
• For OLTP users this ratio will be low. For DW users
this ratio should be higher.
• A high ratio can mean indexing or optimizer issues
(isrd + iswr + isrw + isdl) / (bfr + bfw)

36. Questions