help in compare -display bufferpool and mainview stats



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help in compare -display bufferpool and mainview stats

Postby Gandosio » Fri Jan 24, 2014 2:05 pm

Hi, I need help to understand why i find different values between -display bufferpool(BPn) detail(*) and statistics of mainview.

DSNB401I =DE5P BUFFERPOOL NAME BP2, BUFFERPOOL ID 2, USE COUNT 4336
DSNB402I =DE5P BUFFER POOL SIZE = 30000 BUFFERS AUTOSIZE = NO
ALLOCATED = 30000 TO BE DELETED = 0
IN-USE/UPDATED = 344 BUFFERS ACTIVE = 30000
DSNB406I =DE5P PGFIX ATTRIBUTE -
CURRENT = NO
PENDING = NO
PAGE STEALING METHOD = LRU
DSNB404I =DE5P THRESHOLDS -
VP SEQUENTIAL = 20
DEFERRED WRITE = 30 VERTICAL DEFERRED WRT = 5, 0
PARALLEL SEQUENTIAL =5 ASSISTING PARALLEL SEQT= 0
DSNB410I =DE5P CUMULATIVE STATISTICS SINCE 10:18:06 JAN 19, 2014
DSNB411I =DE5P RANDOM GETPAGE =1387943442 SYNC READ I/O (R) =
23320612
SEQ. GETPAGE = 60511841 SYNC READ I/O (S) = 1100997
DMTH HIT = 0 PAGE-INS REQUIRED = 22339
DSNB412I =DE5P SEQUENTIAL PREFETCH -
REQUESTS = 1269308 PREFETCH I/O = 1241552
PAGES READ = 59311257
DSNB413I =DE5P LIST PREFETCH -
REQUESTS = 4141 PREFETCH I/O = 2919
PAGES READ = 93736

Mainview statistics
24JAN2014 09:15:04 ------ MAINVIEW WINDOW INTERFACE (V6.0.00) ----------------
CURR WIN ===> 1 ALT WIN ===>
W1 =BFRPL====BFRPLD===DE5P=====*========24JAN2014==09:11:45====MVDB2====D====1
Interval Session
Virtual Pool Allocation...........
Buffers Allocated............... 30000
Current Active Buffers.......... 313
Expansions/contractions......... 0 0
No Buffer - Pool Full........... 0 0
Expansion Fail.................. 0 0
Virtual Pool Read Statistics......
Getpages........................ 7264158 1.4G
Sequential Getpages............. 3 60511794
Sync I/O........................ 103420 24342830
Sequential Sync I/O............. 0 1100996
Destructive Reads............... 0 0
Destructive Reads Dequeue....... 0 0
Page-Ins for I/O................ 0 22339
Virtual Pool Write Statistics.....
Async I/O....................... 5504 1379384


Often if I execute Getpages - Sequential Getpages (in mainview) i fine a value quite equal to what i find with display bufferpool at RANDOM GETPAGE (and the value of sequential getpage in mainview ad sequential getpage in display bufferpool are quite equal too).
Sometime instead i find a value of sequential getpage in mainview greater than getpage value (always mainview) so Getpages - seguential getpage = random getpage is impossible. I haven't found the information on what is the interval considerated by mainview, i think the difference could be due to this interval, ...the difference between the values is greater at the end of the day...

Sorry for my english i hope is enough clear what is the problem..
Thanks! for any help...
Gandosio
 
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