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SSD on raid-dp performance issue

[ Edited ]

Hi,

 

I need some advise. We have a new Netapp FAS2552 with Data ONTAP 8.3.1P1 which has two LUNs on raid6, one is from SAS and the second is from SSD disks.

 

The both LUNs are connected by multipath to couple of XenServer 6.5 over 8Gbps FC.

 

Everything is working great except performance of filesystems on SSD. I tried to test performance of virtual filesystems from linux and windows and the results were almost the same, so I guess the issue is not related to VM.

 

Google is full of ideas that everything else of raid1 or raid10 on SSD is performance disaster, but Data ONTAP allow me to create only raid4 and raid-dp (raid 6) arrays.

 

 

Do you have some advice what I missed? Thanks a lot.

Re: SSD on raid-dp performance issue

How big is your SSD Aggr?

Re: SSD on raid-dp performance issue

Hello @pahl,

 

Can you clarify what metric you are using to gauge performance?  Throughput, IOPS, latency?  

 

You said you tested performance of "virtual file systems from Linux and Windows and the results were almost the same".  Can you describe the testing you did?  This will help to determine what bottleneck might be occurring.

 

Lastly, it's safe to assume there are no QoS policies in place?

 

Thanks!

 

Andrew

If this post resolved your issue, please help others by selecting ACCEPT AS SOLUTION or adding a KUDO.

Re: SSD on raid-dp performance issue

[ Edited ]

Hi @JGPSHNTAP

 

the SSD aggr is from 7x 400GB SSD as one raid-dp + 1x spare. All space is dedicated for XenServer.

 

Hi @asulliva

 

ok, I'll describe it in details. I moved our huge DB and SOLR apps to SSD and we didn't notice any rapid improvements, so I went for testing SAS vs SSD.

 

We use CentOS 6.7 as VM in XenServer 6.5, I attached one 20GB FS from SAS LUN and the second one from SSD LUN, 20GB as well. First of all I disabled all caches on VM as:

 

sync; echo 3 > /proc/sys/vm/drop_caches

 

I tested both FS with iozone with O_DIRECT feature, I tried diff file size but I will paste statistics for 1GB file and diff block sizes.

 

Results from Xen FS mounted as /mnt/sas, created on LUN from SAS aggr:

  

	Iozone: Performance Test of File I/O
	        Version $Revision: 3.434 $
		Compiled for 64 bit mode.
		Build: linux-AMD64 

	Contributors:William Norcott, Don Capps, Isom Crawford, Kirby Collins
	             Al Slater, Scott Rhine, Mike Wisner, Ken Goss
	             Steve Landherr, Brad Smith, Mark Kelly, Dr. Alain CYR,
	             Randy Dunlap, Mark Montague, Dan Million, Gavin Brebner,
	             Jean-Marc Zucconi, Jeff Blomberg, Benny Halevy, Dave Boone,
	             Erik Habbinga, Kris Strecker, Walter Wong, Joshua Root,
	             Fabrice Bacchella, Zhenghua Xue, Qin Li, Darren Sawyer,
	             Vangel Bojaxhi, Ben England, Vikentsi Lapa,
	             Alexey Skidanov.

	Run began: Thu Jan 28 10:54:20 2016

	Auto Mode
	O_DIRECT feature enabled
	File size set to 1048576 kB
	Command line used: /opt/iozone/bin/iozone -a -I -s 1g -f /mnt/sas/test
	Output is in kBytes/sec
	Time Resolution = 0.000001 seconds.
	Processor cache size set to 1024 kBytes.
	Processor cache line size set to 32 bytes.
	File stride size set to 17 * record size.
                                                              random    random     bkwd    record    stride                                    
              kB  reclen    write  rewrite    read    reread    read     write     read   rewrite      read   fwrite frewrite    fread  freread
         1048576       4     2407     4524    11770    11247     1602     4528    11187      4637     11335   824989  1019893  2097269  2108950
         1048576       8     4808     8333    21866    21902     1970     8387    19980      8477     20423  1172515  1478819  3058757  3066505
         1048576      16     8794    14918    37052    35695     4193    15944    39035     17266     34981  1447991  1887540  3914044  3914904
         1048576      32    16438    27473    64588    62208     8524    28241    67426     30727     69550  1643718  2308494  4630722  4677574
         1048576      64    28821    44122    90370    99425    14530    46141   115955     52210    112972  1795544  2434902  5072888  5110288
         1048576     128    49998    68656   127044   132931    25200    66784   137641     86565    127569  1867787  2500110  4890767  4895084
         1048576     256    59295    95655   173110   171419    35374    87807   198956    117810    188044  1964890  2719159  4957199  5036557
         1048576     512    95510   102086   252159   269248    53485   129259   225975    179361    354612  1939308  2636070  5082203  5035882
         1048576    1024   158335   150673   229718   297767    86007   148578   290356    225694    353143  1628236  2116098  5114627  5188426
         1048576    2048   157959   162465   322907   333238   124457   159807   188848    230751    421981  1492250  1846718  4934241  5028564
         1048576    4096   165384   172769   351697   385456   216458   178818   217808    268873    312890  1367384  1768435  4740158  4742244
         1048576    8192   167972   186220   394493   359762   261051   189302   250701    274369    349293  1306122  1557074  3454252  3441125
         1048576   16384   163538   188526   367646   414351   319475   194663   270279    317466    378682  1288690  1527761  3208824  3250348

iozone test complete.
 

Results from Xen FS mounted as /mnt/ssd, created on LUN from SSD aggr:

 

	Iozone: Performance Test of File I/O
	        Version $Revision: 3.434 $
		Compiled for 64 bit mode.
		Build: linux-AMD64 

	Contributors:William Norcott, Don Capps, Isom Crawford, Kirby Collins
	             Al Slater, Scott Rhine, Mike Wisner, Ken Goss
	             Steve Landherr, Brad Smith, Mark Kelly, Dr. Alain CYR,
	             Randy Dunlap, Mark Montague, Dan Million, Gavin Brebner,
	             Jean-Marc Zucconi, Jeff Blomberg, Benny Halevy, Dave Boone,
	             Erik Habbinga, Kris Strecker, Walter Wong, Joshua Root,
	             Fabrice Bacchella, Zhenghua Xue, Qin Li, Darren Sawyer,
	             Vangel Bojaxhi, Ben England, Vikentsi Lapa,
	             Alexey Skidanov.

	Run began: Thu Jan 28 13:33:25 2016

	Auto Mode
	O_DIRECT feature enabled
	File size set to 1048576 kB
	Command line used: /opt/iozone/bin/iozone -a -I -s 1g -f /mnt/ssd/test
	Output is in kBytes/sec
	Time Resolution = 0.000001 seconds.
	Processor cache size set to 1024 kBytes.
	Processor cache line size set to 32 bytes.
	File stride size set to 17 * record size.
                                                              random    random     bkwd    record    stride                                    
              kB  reclen    write  rewrite    read    reread    read     write     read   rewrite      read   fwrite frewrite    fread  freread
         1048576       4     2631     4498    11065    12442     6420     4564    12368      5107     12343   814619   988754  2075438  2074979
         1048576       8     5523     9443    22041    21073     9591     8604    19590      9367     21633  1164260  1485054  3068433  3054464
         1048576      16     9472    16488    39491    41895    18754    16578    43030     17681     39783  1426672  1928628  3863494  3884751
         1048576      32    18086    28772    68651    73725    33310    30043    76374     33323     69213  1632403  2170232  4489943  4550418
         1048576      64    30982    48023   113187   118352    53527    48088   115848     55982    115540  1801001  2455337  4914541  4958038
         1048576     128    53914    70535   123458   135770    56458    66182   144178     85769    133518  1905804  2579421  4993718  4991077
         1048576     256    74765    93640   170640   182817    78229    91154   187381    119750    194858  1954551  2654528  4990765  4928259
         1048576     512   114930   118205   308444   324404   110998   125608   260175    180883    339721  1959691  2615960  4889218  4985860
         1048576    1024   146171   144075   334040   364039   151489   153638   225434    238507    470527  1645504  2123944  5090049  5207390
         1048576    2048   141683   160714   407527   476160   250148   169753   280901    299889    578804  1452419  1806565  4974530  5005921
         1048576    4096   156249   172249   446444   497289   350113   183895   391211    267520    553456  1380032  1717465  4747347  4733317
         1048576    8192   139301   177699   534872   497975   429912   162182   427456    277298    500148  1280176  1611310  3511535  3484741
         1048576   16384   149426   186364   523130   518921   458423   170016   463315    215153    499715  1299448  1640304  3274978  3256131

iozone test complete.

 

And yes, there are no QoS policies.

 

Re: SSD on raid-dp performance issue

[ Edited ]

Those are perf statistics from FAS2552 during my tests with iozone:

 

SAS:

 

Write:

CPU    NFS   CIFS   HTTP   Total     Net   kB/s     HDD   kB/s     SSD   kB/s    Tape   kB/s  Cache  Cache    CP  CP   HDD   SSD   OTHER    FCP  iSCSI     FCP   kB/s   iSCSI   kB/s
                                       in    out    read  write    read  write    read  write    age    hit  time  ty  util  util                            in    out      in    out
 47%   3748      0      0    6037    6775   4256    1530      0       0      0       0      0     9    100%    0%  -     3%    0%     421   1868      0     721 112025       0      0
 37%    233      0      0    2306    8049   3555   10713  19485       0      0       0      0     9    100%   43%  Tf    6%    0%       3   2070      0    2192 118387       0      0
 42%    223      0      0    1779    7624   4776     315  48495       0      0       0      0     9    100%  100%  :f    9%    0%      16   1540      0  162497  32699       0      0
 80%    226      0      0    1350    4797   3024    4282 152687       0      0       0      0     9    100%   98%  Fn   30%    0%       3   1121      0  200273     31       0      0
 83%    410      0      0    2004   14560   9097    3767 217687       0      0       0      0     9    100%  100%  :v   40%    0%     187   1407      0  207806     79       0      0
 83%    237      0      0    1284    7265   7143    2833 231896       0      0       0      0     9    100%  100%  Bs   42%    0%       9   1038      0  186358     26       0      0
 81%    115      0      0    1314    6083   4617    8577 265737       0      0       0      0     9    100%  100%  Bn   49%    0%      27   1172      0  189370     42       0      0
 82%     86      0      0    1820    7985   5975    3690 178050       0      0       0      0     9    100%   98%  :    35%    0%     416   1318      0  170606     67       0      0
 85%    175      0      0    1479    8616   5866    4670 166644       0      0       0      0     9    100%   81%  Fs   29%    0%     225   1079      0  192430     28       0      0
 80%    103      0      0    1484    7257   6307    5883 266931       0      0       0      0     9    100%   95%  Fn   50%    0%       6   1375      0  199028     85       0      0
 80%    136      0      0    1436   11509   6769    5085 235628       0      0       0      0     9    100%  100%  :f   42%    0%       0   1300      0  219511    168       0      0
 87%    202      0      0    1282    8967   8620    3722 267325       0      0       0      0     9    100%   98%  Fs   47%    0%      25   1055      0  181347     30       0      0
 78%    141      0      0    1957    7024   5457    5320 192260       0      0       0      0     9    100%   92%  Fn   37%    0%       8   1808      0  200654    111       0      0
 55%    134      0      0     580    8763   4802    4234 216544       0      0       0      0     9    100%  100%  :v   41%    0%       6    440      0   68804     12       0      0
 27%    156      0      0    1475    8363   6353     880     24       0      0       0      0     8s    99%    1%  :     4%    0%       0   1319      0   62081     89       0      0
 27%    174      0      0    1161    7818   7051      28      0       0      0       0      0     8s    98%    0%  -     1%    0%       1    986      0   62071     25       0      0
 39%    322      0      0    1150    7788   6832    5239  33593       0      0       0      0    10     99%   23%  Fn    9%    0%      19    809      0   47708     42       0      0
 39%    408      0      0    1343    6613   6550    3968 106272       0      0       0      0    10     99%  100%  :f   20%    0%      10    925      0   49993     34       0      0
 30%    274      0      0    1168    7972   5482    1604  94928       0      0       0      0    10     98%  100%  :f   17%    0%       0    894      0   53900     22       0      0
 35%    321      0      0    1777   13812   6242    1616  93044       0      0       0      0     0s    98%  100%  :    21%    0%     190   1266      0   58353    100       0      0

Read:

CPU    NFS   CIFS   HTTP   Total     Net   kB/s     HDD   kB/s     SSD   kB/s    Tape   kB/s  Cache  Cache    CP  CP   HDD   SSD   OTHER    FCP  iSCSI     FCP   kB/s   iSCSI   kB/s
                                       in    out    read  write    read  write    read  write    age    hit  time  ty  util  util                            in    out      in    out
 62%    176      0      0     683    6216   6101    8980 111696       0      0       0      0     0s    99%   98%  Ff   38%    0%      16    491      0   58606     47       0      0
 35%    165      0      0     835    7451   6249    5476 102152       0      0       0      0     0s   100%  100%  :f   22%    0%      17    653      0   75593     21       0      0
 41%    172      0      0    1298    6037   5980    6536 102144       0      0       0      0     0s   100%  100%  :f   20%    0%       0   1126      0   88117     77       0      0
 32%    166      0      0     804    6719   5228    6935  26130       0      0       0      0     0s   100%   31%  Fn   10%    0%       2    636      0   76174     15       0      0
 62%    197      0      0    1042    6831   4903    8219 101157       0      0       0      0     9     99%  100%  :f   28%    0%       0    845      0   60438     90       0      0
 38%    353      0      0     988   10004  11262    5112  97280       0      0       0      0     9    100%  100%  :f   19%    0%       0    635      0   76632     17       0      0
 35%    166      0      0     865    5134   5823    6170  97215       0      0       0      0     9    100%  100%  :f   23%    0%      15    684      0   81042     23       0      0
 33%    126      0      0    1015    5457   5378    5083  35690       0      0       0      0     0s   100%   42%  F0   12%    0%       0    889      0   76976     51       0      0
 61%    207      0      0     691    5564   5714   10151 100946       0      0       0      0     9     99%  100%  :f   22%    0%       0    484      0   55476     16       0      0
 40%    254      0      0    1553    4469   4423    7372  92440       0      0       0      0     9     99%  100%  :f   21%    0%     191   1108      0   82704     83       0      0
 31%    203      0      0    1276    5732   5530   98792 111872       0      0       0      0     0s   100%  100%  :f   27%    0%       0   1073      0   13735 103953       0      0
 27%    191      0      0    1272    8825   8657  124240  33664       0      0       0      0     0s   100%   39%  :    18%    0%      15   1066      0     293 126289       0      0
 25%    241      0      0    1595    7257   5907  123184     24       0      0       0      0     0s   100%    0%  -     8%    0%       0   1354      0    1992 125350       0      0
 39%   1785      0      0    2827    8669   6782  118617      0       0      0       0      0     0s   100%    0%  -    10%    0%       0   1042      0    2355 121188       0      0
 37%   1452      0      0    3273    9170  10465  124776      0       0      0       0      0     0s   100%    0%  -    15%    0%       9   1812      0   14839 124659       0      0
 35%   3738      0      0    4951    5580   5724  132680     24       0      0       0      0     0s   100%    0%  -    10%    0%      79   1134      0     295 135268       0      0
 31%   2564      0      0    3718    7515   6129  132616      8       0      0       0      0     0s   100%    0%  -     8%    0%      16   1138      0     407 135596       0      0
 21%    125      0      0    1451    6044   6250   52376      0       0      0       0      0     0s   100%    0%  -     4%    0%       0   1326      0     962 136017       0      0
 27%   1922      0      0    3187    6475   6293   79280     24       0      0       0      0     0s   100%    0%  -     8%    0%       0   1265      0     880 150734       0      0
 40%   2544      0      0    4390    9231   6985  138880      0       0      0       0      0     0s   100%    0%  -    14%    0%     244   1602      0   20385 141347       0      0
 CPU    NFS   CIFS   HTTP   Total     Net   kB/s     HDD   kB/s     SSD   kB/s    Tape   kB/s  Cache  Cache    CP  CP   HDD   SSD   OTHER    FCP  iSCSI     FCP   kB/s   iSCSI   kB/s
                                       in    out    read  write    read  write    read  write    age    hit  time  ty  util  util                            in    out      in    out
 34%   1833      0      0    3646    6005   6013  146948      0       0      0       0      0     0s   100%    0%  -    10%    0%     535   1278      0     384 150474       0      0
 55%   2728      0      0    3773   10638   7492  129697  29174       0      0       0      0     0s   100%   59%  Tf   18%    0%       0   1045      0     664 123045       0      0
 33%    360      0      0    1705    9206   7494  133492  58368       0      0       0      0     0s   100%  100%  :f   19%    0%       1   1344      0    1674 136263       0      0
 36%    359      0      0    1914   12162   9656  124752  53504       0      0       0      0     0s    99%  100%  :f   21%    0%     463   1092      0    2190 126027       0      0
 38%    252      0      0    2725    7131   9339  131296  50208       0      0       0      0     1s    99%  100%  :f   30%    0%    1144   1329      0    4662 131385       0      0
 47%    125      0      0    5808    5930   5845   98350  41678       0      0       0      0     1s   100%   81%  :    14%    0%    4504   1179      0     271 140109       0      0
 15%    443      0      0     956    4751   5373   37752      8       0      0       0      0     1s    98%    0%  -     8%    0%       1    512      0     381  58198       0      0

 

SSD:

 

Write:

 CPU    NFS   CIFS   HTTP   Total     Net   kB/s     HDD   kB/s     SSD   kB/s    Tape   kB/s  Cache  Cache    CP  CP   HDD   SSD   OTHER    FCP  iSCSI     FCP   kB/s   iSCSI   kB/s
                                       in    out    read  write    read  write    read  write    age    hit  time  ty  util  util                            in    out      in    out
 28%    859      0      0    2568    4116    410     488      0   70688      0       0      0     0s   100%    0%  -     7%    1%       0   1709      0     512 191005       0      0
 25%    783      0      0    2604    3749    344    2526     32   62833     16       0      0     0s    99%    6%  Ts    5%    0%      66   1755      0     422 190958       0      0
 56%    707      0      0    2596    3231    250    6506  57857   56669   8697       0      0    13     99%  100%  :f   17%    0%       0   1889      0  240290  48244       0      0
 84%    417      0      0    1688    2226    166    1592   3654   85369 214066       0      0    13     99%   93%  Fs    7%    3%       0   1271      0  174707  30179       0      0
 79%    336      0      0    1797    1772    142    2591   5256   91402 262846       0      0    13    100%   87%  Fn    8%    3%      17   1444      0  202384  30323       0      0
 88%    316      0      0    1431    1743    198      59      0   99925 389161       0      0    13    100%  100%  :s    1%    5%       0   1115      0  154381  23787       0      0
 79%    293      0      0    1540    1528     97    2233   5277   90747 190336       0      0    13    100%   69%  Fn    6%    5%       0   1247      0  167812  26585       0      0
 82%    393      0      0    2494    1939    134    2762   3164   77067 256426       0      0    12    100%  100%  :v   17%    3%     791   1310      0  171449  32858       0      0
 87%    204      0      0    2010    1246     65    4469   2118   92698 277680       0      0    12     99%   73%  Fs   20%    5%     685   1121      0  147883  27113       0      0
 72%    381      0      0    2018    1744    220    2185   3507   80181 155440       0      0    12     99%   79%  F0    7%    2%      22   1615      0  223444  44284       0      0
 90%    365      0      0    1449    1583    121    1340   2502  102751 326020       0      0    12    100%  100%  :s    3%    6%       1   1083      0  144782  24588       0      0
 79%    407      0      0    1801    2449    129    3357   6130   93909 237775       0      0    12    100%   92%  Fn    9%    5%       0   1394      0  186086  38411       0      0
 85%    957      0      0    2225    1732    260      76     32   87881 296044       0      0    11     99%  100%  :s    3%    5%       0   1268      0  174379  24952       0      0
 86%   4308      0      0    5463    2710   1001    2771   5672   84818 243209       0      0    11     99%  100%  Bn    9%    5%       0   1155      0  146436  25579       0      0
 50%    862      0      0    1803    4362    281    2653   2849   82542 204681       0      0    11     97%   57%  :     7%    2%     198    743      0   45774  38361       0      0
 33%   1215      0      0    2774    5444    470     104     24   60184      0       0      0    10     96%    0%  -     3%    0%       0   1559      0   88835  50827       0      0
 31%    881      0      0    2277    6904    279     100      0   60388      0       0      0     9     99%    0%  -     3%    0%       2   1394      0   83070  50832       0      0
 61%    757      0      0    1794    5353    329    3108  23520  108192 219232       0      0     0s    97%   97%  Ff    8%    4%       2   1035      0   58698  37141       0      0
 39%   1007      0      0    2420    5410    329      16    528   86868 107372       0      0     0s    95%  100%  :f    4%    1%       0   1413      0   82615  55316       0      0

Read:

CPU    NFS   CIFS   HTTP   Total     Net   kB/s     HDD   kB/s     SSD   kB/s    Tape   kB/s  Cache  Cache    CP  CP   HDD   SSD   OTHER    FCP  iSCSI     FCP   kB/s   iSCSI   kB/s
                                       in    out    read  write    read  write    read  write    age    hit  time  ty  util  util                            in    out      in    out
 66%    807      0      0    2326    3995    292    1751   3013  232677 200414       0      0     0s    99%   94%  :     7%    4%       1   1518      0   44625 210992       0      0
 42%    950      0      0    2900    4356    404     140      0  331561      0       0      0     0s   100%    0%  -     5%    2%      13   1937      0     811 332558       0      0
 44%    930      0      0    3029    3761    329     176     32  357872      0       0      0     0s    99%    0%  -     5%    2%       0   2099      0     970 355814       0      0
 42%    821      0      0    3117    3543    259     168      0  284936      0       0      0     0s    99%    0%  -     3%    1%       1   2295      0     720 391858       0      0
 43%    524      0      0    2646    2399    210     120      0  363424      0       0      0     0s   100%    0%  -     1%    2%       1   2121      0    1165 363169       0      0
 42%    590      0      0    2704    2636    199      48     24  348304      0       0      0     0s    99%    0%  -     3%    2%       0   2114      0     959 356259       0      0
 34%    697      0      0    2136    4043    219       4      0  157688      0       0      0     0s    94%    0%  -     1%    2%      18   1421      0     599 241312       0      0
 32%    948      0      0    1906    4212    409     164      8  162585      0       0      0     2     90%    0%  -     2%    2%       2    956      0     686 161018       0      0
 28%   1196      0      0    2007    6040    415     156     24  126458      0       0      0     2     91%    0%  -     3%    2%       1    810      0     412 133832       0      0
 26%    706      0      0    1722    3285    283     556      0  124224      0       0      0     2     91%    0%  -     7%    2%     186    830      0    1048 134212       0      0
 31%    796      0      0    1700    4301    251    1741      8  136458     16       0      0     2     91%    5%  Tn    6%    2%       2    902      0     638 149497       0      0
 44%    817      0      0    1797    3817    301    7200  51292  129568  28828       0      0     2     92%  100%  :f   18%    2%      13    967      0     904 154334       0      0
 34%    279      0      0    1509    1613    188      72   4748  161136  64736       0      0     0s    92%  100%  :f    7%    2%       1   1229      0    1500 199148       0      0
 41%   3008      0      0    4138    3624    698     184     64   30012  47640       0      0     0s    98%   70%  :     4%    1%       2   1128      0  163421  37240       0      0
 61%    788      0      0    1831    3511    295    2010  11127   28032  65137       0      0     2    100%   42%  Fn    7%    2%      19   1024      0  166074     76       0      0
 62%    889      0      0    1898    4140    289    2211   6394   68489 250258       0      0     2    100%  100%  :f    7%    3%       2   1007      0  164940    485       0      0
 77%    648      0      0    1348    2815    275    1860   4530   72202 322932       0      0     2    100%   87%  Fn    8%    6%      19    681      0  114332     16       0      0
 59%    602      0      0    1593    3087    282    4842   6582   38518 215484       0      0     0s   100%   87%  :    11%    2%       0    991      0  169396     25       0      0
 71%    503      0      0    1254    3163    173     866   3937   59692 227103       0      0     0s   100%   57%  Fn    5%    6%       4    747      0  127448     18       0      0

Re: SSD on raid-dp performance issue

[ Edited ]

I checked the SAN as well, to see the tests from other side. We have a two redundant FC switches Brocade 5450 on latest FOS 7.3.1b. I did some performance monitoring of all ports on both switches and ran the test against SAS LUN and SSD LUN.

 

I ran both iozone tests from VM Centos 6.7 on XenServer 6.5 on P3. The Netapp FAS2552 is on P21 and P22.

 

When I ran 1st test against SAS, which is LUN on aggr1 and owner is node1, you can see traffic is going through P21, which is right:

When I ran 2nd test against SSD, which is LUN on aggr3 and owner is node2, you can see traffic is going through P22, the results is a little bit better, but not the SSD expected values:

https://drive.google.com/file/d/0B-MNK1FCwbctUWZQTzRXanVTbGs/view?usp=sharing

 

I don't know why, but XenServer or VM is able to generate traffic around 1Gbps from 8Gbps available or Netapp is able to accept only 1Gbps from 8Gbps. The servers and storage is located in one rack, I checked the BB credits and all ports has value 8. There is no Frames Busied, no Frames Rejected and zero Total Errors on all ports.

Re: SSD on raid-dp performance issue

At this point, I would suggest a perfstat and to open a case with Netapp support.   

 

 

Re: SSD on raid-dp performance issue

Hi,

 

Any news on this? We see a similar thing in our environment.

 

Thanks!

 

Gert

Re: SSD on raid-dp performance issue

Similar issue here and case opened, awaiting more information.

Re: SSD on raid-dp performance issue

Hi, Netapp sell 2554 with SSD and when you complain about SSD performance, they said 2554 is a low end model and you should buy the higher model which has more CPU. The 2554 is limited by CPU to provide optimal performance with SSD. That is advise directly from Netapp.