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3.2.1.3 IBM VTS DASD Cache Analysis (TAPLVB)


The CA MICS IBM VTS DASD Cache Analysis Report displays
important VTS DASD cache usage information at an overall VTS
summary level.  If IBM function code FC/4001 is enabled and
the VTS Cache Usage Preference Level (IVTVCU) file is active,
the summary information is broken down and reported at the
individual cache usage preference level.
 
The report provides an excellent view of the DASD cache
utilization, including the average number of virtual volumes
resident, their average size, and total data volume.  Several
different views of volume age are listed (how long volumes
stay in cache), and the quantity of mounts and average
response times are shown by category (total, scratch, cache
hits, and misses).
 
When FC/4001 is enabled and the IVTVCU file is active, this
report provides data useful for evaluating the effectiveness
of preference level setting.  Using preference levels for
virtual volumes supports the automation of separating virtual
volumes into two groups: those that should remain in cache as
long as possible, and those that should be removed from cache
as soon as possible.
 
The report uses the distributed VTS header described in
section 3.2.1.1.2.  Additionally, just above the report body
on the left, the Report Level is listed as either Cache
Summary or Cache Preference Level n.
 
The report body reports on the following measurements from
left to right:
 
Interval count and general cache volume information:
 
o Number of Recording Intervals   - fffAVVIC
o Avg Virtual Volumes in Cache    - fffAVVIC
o Avg Virtual Volume Size (MB)    - fffAVVSZ
o Avg Data Resident in Cache (GB) - fffAVDRC
 
Average age of the virtual volumes in cache:
 
o 4 HR Rolling Avg Virt Vol Age   - fffVA4
o 48 HR Rolling Avg Virt Vol Age  - fffVA48
o 35 Day Rolling Avg Virt Vol Age - fffVA35
 
Total virtual mounts and average mount time:
 
o Total Virtual Mounts    - fffTVM
o Avg Virtual Mount Time  - fffAVVMT
 
Mount counts and mount counts by category:
 
o Virtual Fast-Ready Mounts         - fffVFRM
o Avg Virtual Fast-Ready Mount Time - fffAVFMT
o Virtual Cache-Hit Mounts          - fffVCHM
o Avg Virtual Cache-Hit Mount Time  - fffAVHMT
o Virtual Recall Mounts             - fffVRM
o Avg Virtual Recall Mount Time     - fffAVRMT
 
where fff can be either VDL or VCU
 
At the bottom of the report, a line shows summary totals,
minimums, maximums, averages, or percentages, as appropriate
for the detailed data in each column.
 
Report data for summary cache statistics is generated from
the VTS Distributed Library Activity (IVTVDL) file.  Report
data at the Cache Preference Level is generated from the VTS
Cache Usage Preference Level (IVTVCU) file.

  
To produce the report:
 
  o Enter the CA MICS Workstation Facility (MWF)
 
  o Choose option 2, CA MICS Information Center Facility
    (MICF)
 
  o Choose option 2, Database Inquiries
 
  o Select TAPLVB, IBM VTS DASD Cache Analysis Report,
    whose Catalog Group is PERFORM
 
  o Complete the MICF Execution panel
 
  o Complete the specification panel.  Refer to section
    3.2.1.1.1, IBM VTS MICF Inquiry Specification Panels, for
    information about modifiable panel fields.
 
IBM VTS DASD Cache Analysis (TAPLVB) Report Sample
--------------------------------------------------
The first page of the following report sample shows summary
DASD cache statistics for the User Interface (UI) VTS of a
peer-to-peer configuration.  The site has taken advantage of
advanced cache management, so virtual volumes are stored and
managed in the cache at one of two preference levels.
 
The second and third pages show the breakdown of statistics
for the virtual volumes in cache at each of the two
preference levels.
 
This report sample shows a finely tuned system where the
average size of preference level 0 volumes ("get out fast")
is very large compared to preference level 1 ("stay as long
as possible").
 
Note that the average time in cache for preference level 0 is
much less than that for preference level 1.

 Inquiry : TAPLVB                          CA MICS IBM VTS DASD Cache Analysis Report  Run Date: 02APRyy                             Data Presented by Hour within Day                                         Page 002    VTS Library ID: K9229             Library Make-Model: 3584-L22       Lib Maint Level:  534.33       Report Start: 31MAYyy:00:00  Library Type  : PtP-UI            VTS Cache Size    : 1728 GB        VTS Maint Level: 7414.00       Report End  : 31MAYyy:23:00  Composite ID  : K9200             F/C 4001 Status   : Enabled                                       Timespan    : DAYS   ----------------------------------------------------------------------------------------------------------------------------------                                                             Day: 31MAYyy  Report Level: Cache Summary                            Avg    Avg      --Avg Volume Age---     --- ALL ----     -----------MOUNTS BY CATEGORY------------                  Avg     Vol   Cache                             Cache Mounts     -Fast Ready-   Cache Hits-   -Cache Miss-        Numb    Vols in   Size   Data      4-HR  48-HR  35-DY             Avg             Avg            Avg            Avg  HOUR  Intv     Cache    (MB)   (GB)     HH:MM  HH:MM  HH:MM      Total MM:SS      Total MM:SS   Total MM:SS    Total MM:SS  ----  ----    -------  -----  -----     -----  -----  -----     ------ -----     ------ -----   ----- -----   ------ -----     0     1       5544    392   2122     17:40  17:07  18:00        737  0:04        489  0:02     223  0:02       25  3:38     1     1       5699    387   2156     17:04  17:11  18:00        997  0:05        697  0:02     247  0:02       53  2:34     2     1       5784    387   2187     17:28  17:06  18:00       1300  0:10        885  0:02     349  0:16       66  4:23     3     1       5857    387   2215     18:22  16:54  18:00        564  0:08        411  0:02     111  0:02       42  2:48     4     1       5975    388   2261     16:38  16:54  18:00        669  0:04        432  0:02     209  0:02       28  2:10     5     1       6225    379   2301     14:48  16:58  18:00        815  0:05        484  0:02     279  0:02       52  2:04     6     1       6381    384   2393     13:01  16:57  18:00        465  0:07        281  0:02     156  0:02       28  3:28     7     1       6504    388   2465     13:00  16:57  18:00        495  0:10        283  0:02     164  0:02       48  3:07     8     1       6606    394   2540     17:26  16:55  18:00        606  0:17        385  0:02     165  0:02       56  5:54     9     1       6660    397   2582     20:19  17:18  18:00        316  0:11        202  0:02      89  0:02       25  4:06    10     1       6546    406   2596     23:13  17:16  18:00        162  0:02        109  0:02      49  0:02        4  2:26    11     1       6514    413   2624     24:18  17:28  18:00        114  0:06         79  0:02      28  0:02        7  3:00    12     1       6467    417   2631     24:12  17:29  18:00        162  0:04        116  0:02      40  0:02        6  3:08    13     1       6497    419   2660     25:37  17:32  18:00        256  0:06        156  0:02      84  0:02       16  3:08    14     1       6623    416   2691     26:00  17:31  18:00        290  0:38        157  0:02      31  0:02      102  3:32    15     1       5203    386   1963     19:39  17:34  18:00        720  0:15        510  0:02     127  0:04       83  4:12    16     1       5450    376   2001     19:24  17:30  18:00        907  0:13        721  0:03     124  0:04       62  5:33    17     1       5659    376   2080     17:47  17:27  18:00        817  0:16        617  0:02     134  0:02       66  5:58    18     1       5742    379   2126     17:33  17:33  18:00        853  0:16        626  0:02     150  0:04       77  5:26    19     1       5855    382   2183     15:58  17:31  18:00       1064  0:14        795  0:04     191  0:04       78  5:30    20     1       5906    385   2221     14:28  17:12  18:00        957  0:13        687  0:02     165  0:02      105  3:46    21     1       6110    380   2269     14:30  17:02  18:00        958  0:14        688  0:02     185  0:02       85  4:48    22     1       6181    380   2296     13:02  16:32  18:00        701  0:14        500  0:02     128  0:02       73  4:13        ----    -------  -----  -----     -----  -----  -----     ------ -----     ------ -----   ----- -----   ------ -----  Tots    23       6086    391   2329     18:19  17:13  18:00      14925  0:11      10310  0:02    3428  0:04     1187  4:12 ----------------------------------------------------------------------------------------------------------------------------------


Inquiry : TAPLVB CA MICS IBM VTS DASD Cache Analysis Report Run Date: 02APRyy Data Presented by Hour within Day Page 004 VTS Library ID: K9229 Library Make-Model: 3584-L22 Lib Maint Level: 534.33 Report Start: 31MAYyy:00:00 Library Type : PtP-UI VTS Cache Size : 1728 GB VTS Maint Level: 7414.00 Report End : 31MAYyy:23:00 Composite ID : K9200 F/C 4001 Status : Enabled Timespan : DAYS ---------------------------------------------------------------------------------------------------------------------------------- Day: 31MAYyy Report Level: Cache Preference Level-0 Avg Avg --Avg Volume Age--- --- ALL ---- -----------MOUNTS BY CATEGORY------------ Avg Vol Cache Cache Mounts -Fast Ready- Cache Hits- -Cache Miss- Numb Vols in Size Data 4-HR 48-HR 35-DY Avg Avg Avg Avg HOUR Intv Cache (MB) (GB) HH:MM HH:MM HH:MM Total MM:SS Total MM:SS Total MM:SS Total MM:SS ---- ---- ------- ----- ----- ----- ----- ----- ------ ----- ------ ----- ----- ----- ------ ----- 0 1 145 1229 174 17:20 8:15 6:40 9 1:29 5 0:01 0 0:00 4 3:19 1 1 151 1222 180 1:57 8:13 6:40 12 0:42 8 0:01 0 0:00 4 2:04 2 1 155 1222 185 0:23 8:11 6:40 42 0:19 26 0:02 13 0:18 3 2:45 3 1 160 1253 196 0:37 8:08 6:40 48 0:04 33 0:01 14 0:01 1 2:12 4 1 158 1263 195 0:51 8:08 6:40 11 0:01 8 0:01 3 0:01 0 0:00 5 1 159 1205 187 1:08 8:09 6:40 6 0:11 5 0:01 0 0:00 1 1:01 6 1 160 1196 187 1:18 8:10 6:40 3 0:01 3 0:01 0 0:00 0 0:00 7 1 161 1189 187 1:52 8:09 6:40 2 1:02 1 0:01 0 0:00 1 2:03 8 1 167 1195 195 0:49 8:15 6:40 29 2:03 14 0:01 0 0:00 15 3:56 9 1 172 1179 198 0:13 7:14 6:40 4 1:54 2 0:01 0 0:00 2 3:47 10 1 172 1179 198 0:05 7:29 6:40 0 0:00 0 0:00 0 0:00 0 0:00 11 1 173 1176 199 0:05 7:53 6:40 3 0:01 3 0:01 0 0:00 0 0:00 12 1 175 1169 200 0:07 8:02 6:40 0 0:00 0 0:00 0 0:00 0 0:00 13 1 175 1169 200 0:00 8:11 6:40 0 0:00 0 0:00 0 0:00 0 0:00 14 1 175 1169 200 0:00 8:17 6:40 0 0:00 0 0:00 0 0:00 0 0:00 15 1 85 1183 98 30:08 10:15 6:40 0 0:00 0 0:00 0 0:00 0 0:00 16 1 87 1206 103 29:48 10:20 6:40 25 0:19 23 0:02 0 0:00 2 3:36 17 1 87 1210 103 22:39 10:40 6:40 24 0:08 22 0:01 0 0:00 2 1:29 18 1 94 1213 111 18:55 10:50 6:40 54 0:01 40 0:01 12 0:01 2 0:01 19 1 95 1184 110 1:00 10:29 6:40 42 0:03 38 0:01 3 0:01 1 1:08 20 1 98 1111 106 0:48 10:16 6:40 25 0:18 20 0:01 1 0:02 4 1:47 21 1 92 1135 102 0:54 10:17 6:40 4 0:01 2 0:01 2 0:01 0 0:00 22 1 90 1133 100 0:18 10:17 6:40 3 0:30 2 0:01 0 0:00 1 1:29 ---- ------- ----- ----- ----- ----- ----- ------ ----- ------ ----- ----- ----- ------ ----- Tots 23 139 1191 161 5:42 8:53 6:40 346 0:23 255 0:01 48 0:06 43 2:50 ----------------------------------------------------------------------------------------------------------------------------------


Inquiry : TAPLVB CA MICS IBM VTS DASD Cache Analysis Report Run Date: 02APRyy Data Presented by Hour within Day Page 006 VTS Library ID: K9229 Library Make-Model: 3584-L22 Lib Maint Level: 534.33 Report Start: 31MAYyy:00:00 Library Type : PtP-UI VTS Cache Size : 1728 GB VTS Maint Level: 7414.00 Report End : 31MAYyy:23:00 Composite ID : K9200 F/C 4001 Status : Enabled Timespan : DAYS ---------------------------------------------------------------------------------------------------------------------------------- Day: 31MAYyy Report Level: Cache Preference Level-1 Avg Avg --Avg Volume Age--- --- ALL ---- -----------MOUNTS BY CATEGORY------------ Avg Vol Cache Cache Mounts -Fast Ready- Cache Hits- -Cache Miss- Numb Vols in Size Data 4-HR 48-HR 35-DY Avg Avg Avg Avg HOUR Intv Cache (MB) (GB) HH:MM HH:MM HH:MM Total MM:SS Total MM:SS Total MM:SS Total MM:SS ---- ---- ------- ----- ----- ----- ----- ----- ------ ----- ------ ----- ----- ----- ------ ----- 0 1 5399 369 1948 17:41 17:43 18:36 728 0:04 484 0:01 223 0:01 21 1:32 1 1 5548 365 1975 17:24 17:47 18:36 985 0:05 689 0:01 247 0:01 49 1:13 2 1 5629 364 2002 17:43 17:42 18:36 1258 0:09 859 0:01 336 0:08 63 2:10 3 1 5697 363 2019 18:42 17:30 18:36 508 0:07 374 0:01 97 0:01 37 1:24 4 1 5817 364 2067 16:59 17:30 18:36 658 0:04 424 0:01 206 0:01 28 1:05 5 1 6066 357 2114 15:09 17:34 18:36 809 0:05 479 0:01 279 0:01 51 1:02 6 1 6221 363 2207 13:23 17:33 18:36 462 0:07 278 0:01 156 0:01 28 1:44 7 1 6343 368 2278 13:11 17:33 18:36 493 0:10 282 0:01 164 0:01 47 1:33 8 1 6439 373 2346 17:49 17:30 18:36 577 0:12 371 0:01 165 0:01 41 2:35 9 1 6488 376 2384 20:55 17:58 18:36 312 0:09 200 0:01 89 0:01 23 1:54 10 1 6374 385 2398 23:50 17:54 18:36 162 0:03 109 0:01 49 0:01 4 1:13 11 1 6341 392 2425 24:57 18:03 18:36 111 0:07 76 0:01 28 0:01 7 1:30 12 1 6292 396 2431 24:36 18:03 18:36 162 0:04 116 0:01 40 0:01 6 1:34 13 1 6322 399 2460 25:37 18:05 18:36 256 0:07 156 0:01 84 0:01 16 1:34 14 1 6448 396 2491 26:00 18:03 18:36 286 0:38 153 0:01 31 0:01 102 1:46 15 1 5118 373 1864 19:13 17:59 18:36 720 0:16 510 0:01 127 0:02 83 2:06 16 1 5363 363 1899 19:00 17:54 18:36 882 0:12 698 0:01 124 0:02 60 2:45 17 1 5572 363 1977 17:35 17:48 18:36 793 0:16 595 0:01 134 0:01 64 3:02 18 1 5648 365 2014 17:29 17:54 18:36 799 0:17 586 0:01 138 0:02 75 2:47 19 1 5760 369 2074 16:42 17:53 18:36 1021 0:14 757 0:02 187 0:02 77 2:46 20 1 5808 373 2115 15:14 17:34 18:36 932 0:13 667 0:01 164 0:01 101 1:53 21 1 6018 369 2167 15:12 17:24 18:36 922 0:14 654 0:01 183 0:01 85 2:24 22 1 6091 369 2196 13:33 16:53 18:36 698 0:14 498 0:01 128 0:01 72 2:07 ---- ------- ----- ----- ----- ----- ----- ------ ----- ------ ----- ----- ----- ------ ----- Tots 23 5948 373 2167 18:36 17:44 18:36 14534 0:11 10015 0:01 3379 0:02 1140 2:05 ----------------------------------------------------------------------------------------------------------------------------------

Figure 3-6.  IBM VTS DASD Cache Analysis