HP 3PAR StoreServ 7400 2-node HP 3PAR System Reporter 3.1.0 Software User& - Page 207

Calculating Common Performance Metrics, Table 77 Common Performance Columns

Page 207 highlights

Table 77 Common Performance Columns (continued) Column whist0 d_whist0 ... whist31 d_whist31 rsize0 d_rsize0 ... rsize15 d_rsize15 wrsize0 d_wsize0 ... wsize15 d_wsize15 Type Comment DOUBLE PRECISION Number of writes in service time bucket number 0. NOT NULL DOUBLE PRECISION Difference between whist0 value from last sample for the same object. NOT NULL ... ... DOUBLE PRECISION Number of writes in service time bucket number 31. NOT NULL DOUBLE PRECISION Difference between whist31 value from last sample for same object. NOT NULL DOUBLE PRECISION Number of reads in IO size bucket number 0 (512 bytes). NOT NULL DOUBLE PRECISION Difference between rsize0 value from last sample for the same object. NOT NULL ... ... DOUBLE PRECISION Number of reads in IO size bucket number 15 (16 MiBytes). NOT NULL DOUBLE PRECISION Difference between rsize15 value from last sample for same object. NOT NULL DOUBLE PRECISION Number of writes in IO size bucket number 0 (512 bytes). NOT NULL DOUBLE PRECISION Difference between wsize0 value from last sample for the same object. NOT NULL ... ... DOUBLE PRECISION Number of writes in IO size bucket number 16 (16 MiBytest). NOT NULL DOUBLE PRECISION Difference between wsize15 value from last sample for same object. NOT NULL Although in principle it was not necessary to store the difference values (d_rcount for example), since these can be derived from previous samples of the same object, in practice having the difference values stored in the data tables greatly simplifies the queries and improves the performance of the queries. As described in the comment for the begin column in Table 77 (page 205), the differences are only valid when the objects have the same begin time. Calculating Common Performance Metrics Table 78 (page 207) shows SQL expressions that can be used to calculate various performance metrics from the common performance columns for any sample row. Table 78 Common Performance Metrics for a Sample Row Metric Read IOPs/s Write IOPs/s Total IOPs/s Read KBytes/sec SQL Expression CASE WHEN d_now > 0 THEN d_rcount * 1000000.0/d_now ELSE 0 END CASE WHEN d_now > 0 THEN d_wcount * 1000000.0/d_now ELSE 0 END CASE WHEN d_now > 0 THEN (d_rcount + d_wcount) * 1000000.0/d_now ELSE 0 END CASE WHEN d_now > 0 THEN d_rbytes * 1000.0/d_now ELSE 0 END The Sample Data and Inventory Tables 207

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
  • 213
  • 214
  • 215
  • 216
  • 217
  • 218
  • 219
  • 220
  • 221
  • 222
  • 223
  • 224
  • 225
  • 226
  • 227
  • 228
  • 229
  • 230
  • 231

Table 77 Common Performance Columns
(continued)
Comment
Type
Column
Number of writes in service time bucket number 0.
DOUBLE PRECISION
NOT NULL
whist0
Difference between
whist0
value from last sample for the same object.
DOUBLE PRECISION
NOT NULL
d_whist0
...
...
...
Number of writes in service time bucket number 31.
DOUBLE PRECISION
NOT NULL
whist31
Difference between
whist31
value from last sample for same object.
DOUBLE PRECISION
NOT NULL
d_whist31
Number of reads in IO size bucket number 0 (512 bytes).
DOUBLE PRECISION
NOT NULL
rsize0
Difference between
rsize0
value from last sample for the same object.
DOUBLE PRECISION
NOT NULL
d_rsize0
...
...
...
Number of reads in IO size bucket number 15 (16 MiBytes).
DOUBLE PRECISION
NOT NULL
rsize15
Difference between
rsize15
value from last sample for same object.
DOUBLE PRECISION
NOT NULL
d_rsize15
Number of writes in IO size bucket number 0 (512 bytes).
DOUBLE PRECISION
NOT NULL
wrsize0
Difference between
wsize0
value from last sample for the same object.
DOUBLE PRECISION
NOT NULL
d_wsize0
...
...
...
Number of writes in IO size bucket number 16 (16 MiBytest).
DOUBLE PRECISION
NOT NULL
wsize15
Difference between
wsize15
value from last sample for same object.
DOUBLE PRECISION
NOT NULL
d_wsize15
Although in principle it was not necessary to store the difference values (
d_rcount
for example),
since these can be derived from previous samples of the same object, in practice having the
difference values stored in the data tables greatly simplifies the queries and improves the
performance of the queries. As described in the comment for the
begin
column in
Table 77
(page 205)
, the differences are only valid when the objects have the same
begin
time.
Calculating Common Performance Metrics
Table 78 (page 207)
shows SQL expressions that can be used to calculate various performance
metrics from the common performance columns for any sample row.
Table 78 Common Performance Metrics for a Sample Row
SQL Expression
Metric
CASE WHEN d_now > 0 THEN d_rcount * 1000000.0/d_now ELSE 0 END
Read IOPs/s
CASE WHEN d_now > 0 THEN d_wcount * 1000000.0/d_now ELSE 0 END
Write IOPs/s
CASE WHEN d_now > 0 THEN (d_rcount + d_wcount) * 1000000.0/d_now
ELSE 0 END
Total IOPs/s
CASE WHEN d_now > 0 THEN d_rbytes * 1000.0/d_now ELSE 0 END
Read KBytes/sec
The Sample Data and Inventory Tables
207