Understanding diskspd results

Question

We have a large DB and the cust is complaining that performance is very slow when running searches through the applications interface. It is all supplied by a 3rd party vendor and I've calculated from their guides that the DB will require IoPs of 1300. They don't provide a great deal of info on what that actually means and having just run diskspd I can see it meets the min requirements from the vendor.

Having no context with results to compare against I'm not sure if the latency is good or bad. Can anyone give advice on whether the results below would be ok for you?

The DB is mainly used for searching although it is writing around 450,000 new records per day and currently has around 270 million rows of data.

The DB drives are all NAS based, located on a Netapp NAS connected via 1GB iSCSI over a standard NIC (no HBA was installed by the cust)

I know this probably isn't very helpful but just looking for somewhere to start really?

Command Line: diskspd.exe -b8k -d60 -o4 -t8 -h -r -w25 -L -Z1G -c20G I:\diskspd\iotest.dat

Input parameters:

    timespan:   1
    -------------
    duration: 60s
    warm up time: 5s
    cool down time: 0s
    measuring latency
    random seed: 0
    path: 'I:\diskspd\iotest.dat'
        think time: 0ms
        burst size: 0
        software and hardware write cache disabled
        write buffer size: 1073741824
        performing mix test (write/read ratio: 25/100)
        block size: 8192
        using random I/O (alignment: 8192)
        number of outstanding I/O operations: 4
        thread stride size: 0
        threads per file: 8
        using I/O Completion Ports
        IO priority: normal



Results for timespan 1:
*******************************************************************************

actual test time:   60.00s
thread count:       8
proc count:     32

CPU |  Usage |  User  |  Kernel |  Idle
-------------------------------------------
   0|   8.01%|   2.70%|    5.30%|  91.99%
   1|   8.45%|   1.30%|    7.15%|  91.55%
   2|  52.03%|   2.31%|   49.71%|  47.97%
   3|   4.84%|   0.70%|    4.13%|  95.16%
   4|   7.98%|   2.78%|    5.20%|  92.02%
   5|   7.64%|   2.18%|    5.46%|  92.35%
   6|  10.58%|   5.80%|    4.78%|  89.42%
   7|   4.99%|   0.55%|    4.45%|  95.01%
   8|  11.13%|  10.17%|    0.96%|  88.84%
   9|   0.00%|   0.00%|    0.00%| 100.00%
  10|   5.67%|   5.17%|    0.49%|  94.33%
  11|   0.00%|   0.00%|    0.00%| 100.00%
  12|   8.84%|   7.62%|    1.22%|  91.18%
  13|   0.00%|   0.00%|    0.00%| 100.00%
  14|   9.85%|   9.26%|    0.60%|  90.14%
  15|   0.00%|   0.00%|    0.00%| 100.00%
  16|  11.18%|   9.31%|    1.87%|  88.82%
  17|   0.00%|   0.00%|    0.00%| 100.00%
  18|   8.35%|   6.84%|    1.51%|  91.65%
  19|   0.00%|   0.00%|    0.00%| 100.00%
  20|   2.99%|   2.55%|    0.44%|  97.01%
  21|   0.00%|   0.00%|    0.00%| 100.00%
  22|   3.95%|   3.54%|    0.42%|  96.05%
  23|   0.00%|   0.00%|    0.00%| 100.00%
  24|   0.86%|   0.65%|    0.21%|  99.11%
  25|   0.00%|   0.00%|    0.00%| 100.00%
  26|   0.29%|   0.18%|    0.10%|  99.71%
  27|   0.00%|   0.00%|    0.00%| 100.00%
  28|   0.16%|   0.13%|    0.03%|  99.84%
  29|   0.00%|   0.00%|    0.00%| 100.00%
  30|   0.10%|   0.08%|    0.03%|  99.87%
  31|   0.31%|   0.00%|    0.31%|  99.71%
-------------------------------------------
avg.|   5.26%|   2.31%|    2.95%|  94.74%

Total IO
thread |       bytes     |     I/Os     |     MB/s   |  I/O per s |  AvgLat  | LatStdDev |  file
-----------------------------------------------------------------------------------------------------
     0 |       363053056 |        44318 |       5.77 |     738.64 |    5.386 |    13.446 | I:\diskspd\iotest.dat (20GB)
     1 |       364249088 |        44464 |       5.79 |     741.07 |    5.368 |    13.444 | I:\diskspd\iotest.dat (20GB)
     2 |       347242496 |        42388 |       5.52 |     706.47 |    5.629 |    13.935 | I:\diskspd\iotest.dat (20GB)
     3 |       368271360 |        44955 |       5.85 |     749.26 |    5.310 |    13.273 | I:\diskspd\iotest.dat (20GB)
     4 |       363085824 |        44322 |       5.77 |     738.71 |    5.387 |    13.533 | I:\diskspd\iotest.dat (20GB)
     5 |       363855872 |        44416 |       5.78 |     740.27 |    5.375 |    13.491 | I:\diskspd\iotest.dat (20GB)
     6 |       349626368 |        42679 |       5.56 |     711.32 |    5.594 |    13.958 | I:\diskspd\iotest.dat (20GB)
     7 |       367419392 |        44851 |       5.84 |     747.52 |    5.323 |    13.252 | I:\diskspd\iotest.dat (20GB)
-----------------------------------------------------------------------------------------------------
total:        2886803456 |       352393 |      45.89 |    5873.28 |    5.419 |    13.539

Read IO
thread |       bytes     |     I/Os     |     MB/s   |  I/O per s |  AvgLat  | LatStdDev |  file
-----------------------------------------------------------------------------------------------------
     0 |       272957440 |        33320 |       4.34 |     555.34 |    6.709 |    14.979 | I:\diskspd\iotest.dat (20GB)
     1 |       274038784 |        33452 |       4.36 |     557.54 |    6.619 |    13.939 | I:\diskspd\iotest.dat (20GB)
     2 |       259612672 |        31691 |       4.13 |     528.19 |    6.952 |    14.441 | I:\diskspd\iotest.dat (20GB)
     3 |       276250624 |        33722 |       4.39 |     562.04 |    6.593 |    14.031 | I:\diskspd\iotest.dat (20GB)
     4 |       272154624 |        33222 |       4.33 |     553.71 |    6.639 |    13.532 | I:\diskspd\iotest.dat (20GB)
     5 |       272744448 |        33294 |       4.34 |     554.91 |    6.654 |    14.050 | I:\diskspd\iotest.dat (20GB)
     6 |       263372800 |        32150 |       4.19 |     535.84 |    6.898 |    14.473 | I:\diskspd\iotest.dat (20GB)
     7 |       275447808 |        33624 |       4.38 |     560.41 |    6.618 |    14.263 | I:\diskspd\iotest.dat (20GB)
-----------------------------------------------------------------------------------------------------
total:        2166579200 |       264475 |      34.44 |    4407.96 |    6.708 |    14.217

Write IO
thread |       bytes     |     I/Os     |     MB/s   |  I/O per s |  AvgLat  | LatStdDev |  file
-----------------------------------------------------------------------------------------------------
     0 |        90095616 |        10998 |       1.43 |     183.30 |    1.378 |     5.236 | I:\diskspd\iotest.dat (20GB)
     1 |        90210304 |        11012 |       1.43 |     183.54 |    1.570 |    10.972 | I:\diskspd\iotest.dat (20GB)
     2 |        87629824 |        10697 |       1.39 |     178.29 |    1.708 |    11.449 | I:\diskspd\iotest.dat (20GB)
     3 |        92020736 |        11233 |       1.46 |     187.22 |    1.459 |     9.707 | I:\diskspd\iotest.dat (20GB)
     4 |        90931200 |        11100 |       1.45 |     185.00 |    1.640 |    12.826 | I:\diskspd\iotest.dat (20GB)
     5 |        91111424 |        11122 |       1.45 |     185.37 |    1.546 |    10.786 | I:\diskspd\iotest.dat (20GB)
     6 |        86253568 |        10529 |       1.37 |     175.49 |    1.611 |    11.359 | I:\diskspd\iotest.dat (20GB)
     7 |        91971584 |        11227 |       1.46 |     187.12 |    1.447 |     8.498 | I:\diskspd\iotest.dat (20GB)
-----------------------------------------------------------------------------------------------------
total:         720224256 |        87918 |      11.45 |    1465.32 |    1.544 |    10.328

Answer 1

Is the DB on a SATA aggregate or a SAS aggregate? The dskspd test you are running will get inaccurate results from a netapp due to its caching and nvram architecture...