Início / dba / Perguntas / 5485
Accepted
RThomas
Asked: 2011-09-08 08:46:38 +0800 CST

Conselho de configuração de disco SQL - TempDB, Log DB, questão de posicionamento de arquivo de dados

  • 772

Temos um servidor de banco de dados muito ativo com uma coleção eclética de aplicativos em execução. Dois dos mais ocupados são um banco de dados Laserfiche que faz digitalização de documentos e processamento de fluxo de trabalho durante todo o dia (média de cerca de 2800 solicitações em lote / segundo) e um aplicativo de servidor blackberry que roteia e-mails. Existem também cerca de 25 outros bancos de dados de pequenos aplicativos.

Como somos uma agência governamental, recebemos apenas o orçamento para uma única licença de servidor de banco de dados.

Recentemente, recebemos uma SAN para resolver problemas de contenção de disco.

Portanto, atualmente temos o TempDB em execução em seu próprio disco (raid 1 par de espelhos) e movemos os logs de transação e os arquivos de dados para a SAN. Os logs de transação foram colocados em um local lógico e os arquivos de dados em outro. Fisicamente, é o mesmo array, mas é um array composto por 14 eixos totais (discos) em uma configuração raid 1+0.

Um SAN bastante robusto - e as coisas estão funcionando muito melhor. Comprimentos de fila cortados pela metade.

Só hoje também nos foi dada outra opção. Também poderíamos ter uma matriz de 4 discos se precisássemos dela atualmente no servidor de arquivos. Eu sei que ter MDF e LDF em duas matrizes separadas é geralmente recomendado, mas a única maneira de fazer isso em nossa situação seria mover dados ou logs de transação da SAN para a matriz de 4 discos configurada como Raid 5. Lembre-se de que eles são atualmente em volumes lógicos separados, mas compartilhando o mesmo array físico.

Atirando do quadril, sinto que ter os MDFs e LDFs juntos em uma matriz de raid 1 + 0 de 14 fusos é provavelmente tão bom quanto tê-los separados com um em uma matriz de raid 5 de 4 fusos. Mas eu não estaria aqui perguntando se sou um especialista em lógica de disco. Ambas as opções estão usando discos SAS de 15k basicamente idênticos - ou seja, cada eixo é basicamente idêntico.

Então, em essência, a questão é. Ter MDF / LDF em um único array de 14 eixos configurado como raid 1 + 0 será melhorado por qualquer margem significativa (ou de todo) movendo dados ou log para seu próprio array de 4 eixos raid 5?

Pensamentos?

INFORMAÇÕES ATUALIZADAS:

Também observarei que atualmente o comprimento médio da fila no volume de log permanece bastante consistente em torno de 0,55. O comprimento médio da fila no volume de dados raramente é superior a 0,01 (geralmente 0,00)

sys.dm_io_virtual_file_stats RESULTADO DA CONSULTA:

<table>
 <tr>
  <td>database
  id</td>
  <td>Volume</td>
  <td>io_stall_read_ms</td>
  <td>num_of_reads</td>
  <td>avg_read_stall_ms</td>
  <td>io_stall_write_ms</td>
  <td>num_of_writes</td>
  <td>avg_write_stall_ms</td>
  <td>io_stalls</td>
  <td>total_io</td>
  <td>avg_io_stall_ms</td>
 </tr>
 <tr>
  <td>25</td>
  <td>h</td>
  <td>175086</td>
  <td>1411</td>
  <td>124</td>
  <td>69</td>
  <td>41</td>
  <td>1.6</td>
  <td>175155</td>
  <td>1452</td>
  <td>120.5</td>
 </tr>
 <tr>
  <td>16</td>
  <td>h</td>
  <td>54691</td>
  <td>748</td>
  <td>73</td>
  <td>34</td>
  <td>23</td>
  <td>1.4</td>
  <td>54725</td>
  <td>771</td>
  <td>70.9</td>
 </tr>
 <tr>
  <td>41</td>
  <td>h</td>
  <td>192255</td>
  <td>982</td>
  <td>195.6</td>
  <td>5232</td>
  <td>2142</td>
  <td>2.4</td>
  <td>197487</td>
  <td>3124</td>
  <td>63.2</td>
 </tr>
 <tr>
  <td>24</td>
  <td>h</td>
  <td>8616</td>
  <td>178</td>
  <td>48.1</td>
  <td>55</td>
  <td>22</td>
  <td>2.4</td>
  <td>8671</td>
  <td>200</td>
  <td>43.1</td>
 </tr>
 <tr>
  <td>29</td>
  <td>h</td>
  <td>54617</td>
  <td>1247</td>
  <td>43.8</td>
  <td>71</td>
  <td>41</td>
  <td>1.7</td>
  <td>54688</td>
  <td>1288</td>
  <td>42.4</td>
 </tr>
 <tr>
  <td>40</td>
  <td>h</td>
  <td>132664</td>
  <td>3158</td>
  <td>42</td>
  <td>184</td>
  <td>85</td>
  <td>2.1</td>
  <td>132848</td>
  <td>3243</td>
  <td>41</td>
 </tr>
 <tr>
  <td>15</td>
  <td>h</td>
  <td>26556</td>
  <td>763</td>
  <td>34.8</td>
  <td>33</td>
  <td>23</td>
  <td>1.4</td>
  <td>26589</td>
  <td>786</td>
  <td>33.8</td>
 </tr>
 <tr>
  <td>37</td>
  <td>h</td>
  <td>6943152</td>
  <td>500214</td>
  <td>13.9</td>
  <td>310706380</td>
  <td>9083273</td>
  <td>34.2</td>
  <td>317649532</td>
  <td>9583487</td>
  <td>33.1</td>
 </tr>
 <tr>
  <td>32</td>
  <td>h</td>
  <td>14832</td>
  <td>426</td>
  <td>34.7</td>
  <td>42</td>
  <td>38</td>
  <td>1.1</td>
  <td>14874</td>
  <td>464</td>
  <td>32</td>
 </tr>
 <tr>
  <td>43</td>
  <td>h</td>
  <td>46937</td>
  <td>947</td>
  <td>49.5</td>
  <td>1203</td>
  <td>844</td>
  <td>1.4</td>
  <td>48140</td>
  <td>1791</td>
  <td>26.9</td>
 </tr>
 <tr>
  <td>17</td>
  <td>h</td>
  <td>23166</td>
  <td>786</td>
  <td>29.4</td>
  <td>260</td>
  <td>125</td>
  <td>2.1</td>
  <td>23426</td>
  <td>911</td>
  <td>25.7</td>
 </tr>
 <tr>
  <td>44</td>
  <td>h</td>
  <td>65563</td>
  <td>2968</td>
  <td>22.1</td>
  <td>451</td>
  <td>334</td>
  <td>1.3</td>
  <td>66014</td>
  <td>3302</td>
  <td>20</td>
 </tr>
 <tr>
  <td>27</td>
  <td>h</td>
  <td>73622</td>
  <td>3325</td>
  <td>22.1</td>
  <td>547</td>
  <td>483</td>
  <td>1.1</td>
  <td>74169</td>
  <td>3808</td>
  <td>19.5</td>
 </tr>
 <tr>
  <td>31</td>
  <td>h</td>
  <td>19557</td>
  <td>978</td>
  <td>20</td>
  <td>218</td>
  <td>128</td>
  <td>1.7</td>
  <td>19775</td>
  <td>1106</td>
  <td>17.9</td>
 </tr>
 <tr>
  <td>13</td>
  <td>h</td>
  <td>5238308</td>
  <td>176396</td>
  <td>29.7</td>
  <td>70537264</td>
  <td>4109175</td>
  <td>17.2</td>
  <td>75775572</td>
  <td>4285571</td>
  <td>17.7</td>
 </tr>
 <tr>
  <td>26</td>
  <td>h</td>
  <td>849303</td>
  <td>57475</td>
  <td>14.8</td>
  <td>496337</td>
  <td>19098</td>
  <td>26</td>
  <td>1345640</td>
  <td>76573</td>
  <td>17.6</td>
 </tr>
 <tr>
  <td>28</td>
  <td>h</td>
  <td>12707</td>
  <td>799</td>
  <td>15.9</td>
  <td>103</td>
  <td>62</td>
  <td>1.6</td>
  <td>12810</td>
  <td>861</td>
  <td>14.9</td>
 </tr>
 <tr>
  <td>42</td>
  <td>h</td>
  <td>28630</td>
  <td>1233</td>
  <td>23.2</td>
  <td>1139</td>
  <td>883</td>
  <td>1.3</td>
  <td>29769</td>
  <td>2116</td>
  <td>14.1</td>
 </tr>
 <tr>
  <td>14</td>
  <td>h</td>
  <td>91425</td>
  <td>5480</td>
  <td>16.7</td>
  <td>3762</td>
  <td>2470</td>
  <td>1.5</td>
  <td>95187</td>
  <td>7950</td>
  <td>12</td>
 </tr>
 <tr>
  <td>35</td>
  <td>h</td>
  <td>8253</td>
  <td>546</td>
  <td>15.1</td>
  <td>193</td>
  <td>174</td>
  <td>1.1</td>
  <td>8446</td>
  <td>720</td>
  <td>11.7</td>
 </tr>
 <tr>
  <td>12</td>
  <td>h</td>
  <td>33008</td>
  <td>1852</td>
  <td>17.8</td>
  <td>2179</td>
  <td>1335</td>
  <td>1.6</td>
  <td>35187</td>
  <td>3187</td>
  <td>11</td>
 </tr>
 <tr>
  <td>36</td>
  <td>h</td>
  <td>4322</td>
  <td>470</td>
  <td>9.2</td>
  <td>150</td>
  <td>119</td>
  <td>1.3</td>
  <td>4472</td>
  <td>589</td>
  <td>7.6</td>
 </tr>
 <tr>
  <td>6</td>
  <td>h</td>
  <td>537</td>
  <td>61</td>
  <td>8.7</td>
  <td>21</td>
  <td>22</td>
  <td>0.9</td>
  <td>558</td>
  <td>83</td>
  <td>6.6</td>
 </tr>
 <tr>
  <td>33</td>
  <td>h</td>
  <td>4172</td>
  <td>585</td>
  <td>7.1</td>
  <td>63</td>
  <td>59</td>
  <td>1.1</td>
  <td>4235</td>
  <td>644</td>
  <td>6.6</td>
 </tr>
 <tr>
  <td>30</td>
  <td>h</td>
  <td>633</td>
  <td>71</td>
  <td>8.8</td>
  <td>57</td>
  <td>38</td>
  <td>1.5</td>
  <td>690</td>
  <td>109</td>
  <td>6.3</td>
 </tr>
 <tr>
  <td>10</td>
  <td>h</td>
  <td>479</td>
  <td>65</td>
  <td>7.3</td>
  <td>63</td>
  <td>22</td>
  <td>2.7</td>
  <td>542</td>
  <td>87</td>
  <td>6.2</td>
 </tr>
 <tr>
  <td>38</td>
  <td>h</td>
  <td>635</td>
  <td>70</td>
  <td>8.9</td>
  <td>54</td>
  <td>40</td>
  <td>1.3</td>
  <td>689</td>
  <td>110</td>
  <td>6.2</td>
 </tr>
 <tr>
  <td>19</td>
  <td>h</td>
  <td>867</td>
  <td>125</td>
  <td>6.9</td>
  <td>133</td>
  <td>40</td>
  <td>3.2</td>
  <td>1000</td>
  <td>165</td>
  <td>6</td>
 </tr>
 <tr>
  <td>20</td>
  <td>h</td>
  <td>2157</td>
  <td>342</td>
  <td>6.3</td>
  <td>107</td>
  <td>37</td>
  <td>2.8</td>
  <td>2264</td>
  <td>379</td>
  <td>6</td>
 </tr>
 <tr>
  <td>18</td>
  <td>h</td>
  <td>655</td>
  <td>84</td>
  <td>7.7</td>
  <td>109</td>
  <td>44</td>
  <td>2.4</td>
  <td>764</td>
  <td>128</td>
  <td>5.9</td>
 </tr>
 <tr>
  <td>9</td>
  <td>h</td>
  <td>22017</td>
  <td>1269</td>
  <td>17.3</td>
  <td>12187</td>
  <td>4510</td>
  <td>2.7</td>
  <td>34204</td>
  <td>5779</td>
  <td>5.9</td>
 </tr>
 <tr>
  <td>11</td>
  <td>h</td>
  <td>1641</td>
  <td>226</td>
  <td>7.2</td>
  <td>158</td>
  <td>94</td>
  <td>1.7</td>
  <td>1799</td>
  <td>320</td>
  <td>5.6</td>
 </tr>
 <tr>
  <td>7</td>
  <td>h</td>
  <td>556</td>
  <td>66</td>
  <td>8.3</td>
  <td>40</td>
  <td>40</td>
  <td>1</td>
  <td>596</td>
  <td>106</td>
  <td>5.6</td>
 </tr>
 <tr>
  <td>20</td>
  <td>t</td>
  <td>639</td>
  <td>90</td>
  <td>7</td>
  <td>118</td>
  <td>43</td>
  <td>2.7</td>
  <td>757</td>
  <td>133</td>
  <td>5.6</td>
 </tr>
 <tr>
  <td>24</td>
  <td>t</td>
  <td>1031</td>
  <td>167</td>
  <td>6.1</td>
  <td>67</td>
  <td>29</td>
  <td>2.2</td>
  <td>1098</td>
  <td>196</td>
  <td>5.6</td>
 </tr>
 <tr>
  <td>25</td>
  <td>t</td>
  <td>1269</td>
  <td>210</td>
  <td>6</td>
  <td>111</td>
  <td>47</td>
  <td>2.3</td>
  <td>1380</td>
  <td>257</td>
  <td>5.3</td>
 </tr>
 <tr>
  <td>29</td>
  <td>t</td>
  <td>680</td>
  <td>94</td>
  <td>7.2</td>
  <td>113</td>
  <td>54</td>
  <td>2.1</td>
  <td>793</td>
  <td>148</td>
  <td>5.3</td>
 </tr>
 <tr>
  <td>30</td>
  <td>t</td>
  <td>233</td>
  <td>25</td>
  <td>9</td>
  <td>145</td>
  <td>47</td>
  <td>3</td>
  <td>378</td>
  <td>72</td>
  <td>5.2</td>
 </tr>
 <tr>
  <td>13</td>
  <td>t</td>
  <td>11947937</td>
  <td>55092</td>
  <td>216.9</td>
  <td>163346886</td>
  <td>33789532</td>
  <td>4.8</td>
  <td>175294823</td>
  <td>33844624</td>
  <td>5.2</td>
 </tr>
 <tr>
  <td>15</td>
  <td>t</td>
  <td>693</td>
  <td>119</td>
  <td>5.8</td>
  <td>82</td>
  <td>29</td>
  <td>2.7</td>
  <td>775</td>
  <td>148</td>
  <td>5.2</td>
 </tr>
 <tr>
  <td>16</td>
  <td>t</td>
  <td>731</td>
  <td>119</td>
  <td>6.1</td>
  <td>48</td>
  <td>29</td>
  <td>1.6</td>
  <td>779</td>
  <td>148</td>
  <td>5.2</td>
 </tr>
 <tr>
  <td>29</td>
  <td>h</td>
  <td>176</td>
  <td>34</td>
  <td>5</td>
  <td>1</td>
  <td>1</td>
  <td>0.5</td>
  <td>177</td>
  <td>35</td>
  <td>4.9</td>
 </tr>
 <tr>
  <td>18</td>
  <td>t</td>
  <td>305</td>
  <td>44</td>
  <td>6.8</td>
  <td>165</td>
  <td>52</td>
  <td>3.1</td>
  <td>470</td>
  <td>96</td>
  <td>4.8</td>
 </tr>
 <tr>
  <td>5</td>
  <td>h</td>
  <td>500</td>
  <td>75</td>
  <td>6.6</td>
  <td>60</td>
  <td>40</td>
  <td>1.5</td>
  <td>560</td>
  <td>115</td>
  <td>4.8</td>
 </tr>
 <tr>
  <td>8</td>
  <td>t</td>
  <td>462</td>
  <td>74</td>
  <td>6.2</td>
  <td>118</td>
  <td>48</td>
  <td>2.4</td>
  <td>580</td>
  <td>122</td>
  <td>4.7</td>
 </tr>
 <tr>
  <td>5</td>
  <td>t</td>
  <td>294</td>
  <td>33</td>
  <td>8.6</td>
  <td>80</td>
  <td>47</td>
  <td>1.7</td>
  <td>374</td>
  <td>80</td>
  <td>4.6</td>
 </tr>
 <tr>
  <td>3</td>
  <td>h</td>
  <td>520</td>
  <td>109</td>
  <td>4.7</td>
  <td>3</td>
  <td>4</td>
  <td>0.6</td>
  <td>523</td>
  <td>113</td>
  <td>4.6</td>
 </tr>
 <tr>
  <td>39</td>
  <td>h</td>
  <td>394</td>
  <td>62</td>
  <td>6.3</td>
  <td>77</td>
  <td>40</td>
  <td>1.9</td>
  <td>471</td>
  <td>102</td>
  <td>4.6</td>
 </tr>
 <tr>
  <td>39</td>
  <td>t</td>
  <td>124</td>
  <td>16</td>
  <td>7.3</td>
  <td>165</td>
  <td>47</td>
  <td>3.4</td>
  <td>289</td>
  <td>63</td>
  <td>4.5</td>
 </tr>
 <tr>
  <td>8</td>
  <td>h</td>
  <td>459</td>
  <td>78</td>
  <td>5.8</td>
  <td>93</td>
  <td>43</td>
  <td>2.1</td>
  <td>552</td>
  <td>121</td>
  <td>4.5</td>
 </tr>
 <tr>
  <td>41</td>
  <td>t</td>
  <td>8295</td>
  <td>470</td>
  <td>17.6</td>
  <td>4035</td>
  <td>2359</td>
  <td>1.7</td>
  <td>12330</td>
  <td>2829</td>
  <td>4.4</td>
 </tr>
 <tr>
  <td>31</td>
  <td>t</td>
  <td>637</td>
  <td>91</td>
  <td>6.9</td>
  <td>170</td>
  <td>95</td>
  <td>1.8</td>
  <td>807</td>
  <td>186</td>
  <td>4.3</td>
 </tr>
 <tr>
  <td>7</td>
  <td>t</td>
  <td>242</td>
  <td>29</td>
  <td>8.1</td>
  <td>80</td>
  <td>47</td>
  <td>1.7</td>
  <td>322</td>
  <td>76</td>
  <td>4.2</td>
 </tr>
 <tr>
  <td>22</td>
  <td>h</td>
  <td>298</td>
  <td>80</td>
  <td>3.7</td>
  <td>0</td>
  <td>1</td>
  <td>0</td>
  <td>298</td>
  <td>81</td>
  <td>3.6</td>
 </tr>
 <tr>
  <td>38</td>
  <td>t</td>
  <td>139</td>
  <td>22</td>
  <td>6</td>
  <td>115</td>
  <td>47</td>
  <td>2.4</td>
  <td>254</td>
  <td>69</td>
  <td>3.6</td>
 </tr>
 <tr>
  <td>40</td>
  <td>t</td>
  <td>1016</td>
  <td>159</td>
  <td>6.4</td>
  <td>388</td>
  <td>236</td>
  <td>1.6</td>
  <td>1404</td>
  <td>395</td>
  <td>3.5</td>
 </tr>
 <tr>
  <td>22</td>
  <td>t</td>
  <td>76</td>
  <td>18</td>
  <td>4</td>
  <td>7</td>
  <td>5</td>
  <td>1.2</td>
  <td>83</td>
  <td>23</td>
  <td>3.5</td>
 </tr>
 <tr>
  <td>44</td>
  <td>t</td>
  <td>873</td>
  <td>133</td>
  <td>6.5</td>
  <td>479</td>
  <td>263</td>
  <td>1.8</td>
  <td>1352</td>
  <td>396</td>
  <td>3.4</td>
 </tr>
 <tr>
  <td>4</td>
  <td>h</td>
  <td>10565</td>
  <td>2057</td>
  <td>5.1</td>
  <td>2840</td>
  <td>2061</td>
  <td>1.4</td>
  <td>13405</td>
  <td>4118</td>
  <td>3.3</td>
 </tr>
 <tr>
  <td>32</td>
  <td>t</td>
  <td>94</td>
  <td>18</td>
  <td>4.9</td>
  <td>72</td>
  <td>33</td>
  <td>2.1</td>
  <td>166</td>
  <td>51</td>
  <td>3.2</td>
 </tr>
 <tr>
  <td>19</td>
  <td>t</td>
  <td>116</td>
  <td>16</td>
  <td>6.8</td>
  <td>116</td>
  <td>60</td>
  <td>1.9</td>
  <td>232</td>
  <td>76</td>
  <td>3</td>
 </tr>
 <tr>
  <td>11</td>
  <td>t</td>
  <td>144</td>
  <td>18</td>
  <td>7.6</td>
  <td>181</td>
  <td>91</td>
  <td>2</td>
  <td>325</td>
  <td>109</td>
  <td>3</td>
 </tr>
 <tr>
  <td>10</td>
  <td>t</td>
  <td>69</td>
  <td>12</td>
  <td>5.3</td>
  <td>48</td>
  <td>29</td>
  <td>1.6</td>
  <td>117</td>
  <td>41</td>
  <td>2.8</td>
 </tr>
 <tr>
  <td>6</td>
  <td>t</td>
  <td>69</td>
  <td>11</td>
  <td>5.8</td>
  <td>40</td>
  <td>29</td>
  <td>1.3</td>
  <td>109</td>
  <td>40</td>
  <td>2.7</td>
 </tr>
 <tr>
  <td>1</td>
  <td>h</td>
  <td>941</td>
  <td>181</td>
  <td>5.2</td>
  <td>368</td>
  <td>356</td>
  <td>1</td>
  <td>1309</td>
  <td>537</td>
  <td>2.4</td>
 </tr>
 <tr>
  <td>9</td>
  <td>t</td>
  <td>5034</td>
  <td>394</td>
  <td>12.7</td>
  <td>9584</td>
  <td>5599</td>
  <td>1.7</td>
  <td>14618</td>
  <td>5993</td>
  <td>2.4</td>
 </tr>
 <tr>
  <td>17</td>
  <td>t</td>
  <td>1335</td>
  <td>213</td>
  <td>6.2</td>
  <td>1293</td>
  <td>1119</td>
  <td>1.2</td>
  <td>2628</td>
  <td>1332</td>
  <td>2</td>
 </tr>
 <tr>
  <td>3</td>
  <td>h</td>
  <td>21</td>
  <td>6</td>
  <td>3</td>
  <td>15</td>
  <td>13</td>
  <td>1.1</td>
  <td>36</td>
  <td>19</td>
  <td>1.8</td>
 </tr>
 <tr>
  <td>34</td>
  <td>h</td>
  <td>1140</td>
  <td>132</td>
  <td>8.6</td>
  <td>4146</td>
  <td>2921</td>
  <td>1.4</td>
  <td>5286</td>
  <td>3053</td>
  <td>1.7</td>
 </tr>
 <tr>
  <td>14</td>
  <td>t</td>
  <td>714</td>
  <td>111</td>
  <td>6.4</td>
  <td>10175</td>
  <td>6589</td>
  <td>1.5</td>
  <td>10889</td>
  <td>6700</td>
  <td>1.6</td>
 </tr>
 <tr>
  <td>42</td>
  <td>t</td>
  <td>949</td>
  <td>139</td>
  <td>6.8</td>
  <td>3420</td>
  <td>2671</td>
  <td>1.3</td>
  <td>4369</td>
  <td>2810</td>
  <td>1.6</td>
 </tr>
 <tr>
  <td>37</td>
  <td>t</td>
  <td>4006</td>
  <td>489</td>
  <td>8.2</td>
  <td>15548682</td>
  <td>9892846</td>
  <td>1.6</td>
  <td>15552688</td>
  <td>9893335</td>
  <td>1.6</td>
 </tr>
 <tr>
  <td>2</td>
  <td>f</td>
  <td>164348</td>
  <td>106669</td>
  <td>1.5</td>
  <td>178498</td>
  <td>121970</td>
  <td>1.5</td>
  <td>342846</td>
  <td>228639</td>
  <td>1.5</td>
 </tr>
 <tr>
  <td>28</td>
  <td>t</td>
  <td>1305</td>
  <td>194</td>
  <td>6.7</td>
  <td>7006</td>
  <td>5797</td>
  <td>1.2</td>
  <td>8311</td>
  <td>5991</td>
  <td>1.4</td>
 </tr>
 <tr>
  <td>45</td>
  <td>h</td>
  <td>123</td>
  <td>93</td>
  <td>1.3</td>
  <td>510</td>
  <td>373</td>
  <td>1.4</td>
  <td>633</td>
  <td>466</td>
  <td>1.4</td>
 </tr>
 <tr>
  <td>43</td>
  <td>t</td>
  <td>1243</td>
  <td>130</td>
  <td>9.5</td>
  <td>13330</td>
  <td>10836</td>
  <td>1.2</td>
  <td>14573</td>
  <td>10966</td>
  <td>1.3</td>
 </tr>
 <tr>
  <td>35</td>
  <td>t</td>
  <td>329</td>
  <td>47</td>
  <td>6.9</td>
  <td>25471</td>
  <td>19582</td>
  <td>1.3</td>
  <td>25800</td>
  <td>19629</td>
  <td>1.3</td>
 </tr>
 <tr>
  <td>27</td>
  <td>t</td>
  <td>1866</td>
  <td>294</td>
  <td>6.3</td>
  <td>12196</td>
  <td>10243</td>
  <td>1.2</td>
  <td>14062</td>
  <td>10537</td>
  <td>1.3</td>
 </tr>
 <tr>
  <td>12</td>
  <td>t</td>
  <td>13789</td>
  <td>2852</td>
  <td>4.8</td>
  <td>28818</td>
  <td>29040</td>
  <td>1</td>
  <td>42607</td>
  <td>31892</td>
  <td>1.3</td>
 </tr>
 <tr>
  <td>4</td>
  <td>t</td>
  <td>511</td>
  <td>67</td>
  <td>7.5</td>
  <td>158330</td>
  <td>130742</td>
  <td>1.2</td>
  <td>158841</td>
  <td>130809</td>
  <td>1.2</td>
 </tr>
 <tr>
  <td>34</td>
  <td>t</td>
  <td>99</td>
  <td>13</td>
  <td>7.1</td>
  <td>134764</td>
  <td>112984</td>
  <td>1.2</td>
  <td>134863</td>
  <td>112997</td>
  <td>1.2</td>
 </tr>
 <tr>
  <td>2</td>
  <td>f</td>
  <td>23</td>
  <td>147</td>
  <td>0.2</td>
  <td>17980</td>
  <td>16879</td>
  <td>1.1</td>
  <td>18003</td>
  <td>17026</td>
  <td>1.1</td>
 </tr>
 <tr>
  <td>1</td>
  <td>h</td>
  <td>54</td>
  <td>10</td>
  <td>4.9</td>
  <td>1845</td>
  <td>1761</td>
  <td>1</td>
  <td>1899</td>
  <td>1771</td>
  <td>1.1</td>
 </tr>
 <tr>
  <td>33</td>
  <td>t</td>
  <td>220</td>
  <td>33</td>
  <td>6.5</td>
  <td>746</td>
  <td>980</td>
  <td>0.8</td>
  <td>966</td>
  <td>1013</td>
  <td>1</td>
 </tr>
 <tr>
  <td>36</td>
  <td>t</td>
  <td>199</td>
  <td>27</td>
  <td>7.1</td>
  <td>26330</td>
  <td>25429</td>
  <td>1</td>
  <td>26529</td>
  <td>25456</td>
  <td>1</td>
 </tr>
 <tr>
  <td>45</td>
  <td>t</td>
  <td>5</td>
  <td>8</td>
  <td>0.6</td>
  <td>6306</td>
  <td>6142</td>
  <td>1</td>
  <td>6311</td>
  <td>6150</td>
  <td>1</td>
 </tr>
 <tr>
  <td>26</td>
  <td>t</td>
  <td>2969</td>
  <td>348</td>
  <td>8.5</td>
  <td>64557</td>
  <td>70819</td>
  <td>0.9</td>
  <td>67526</td>
  <td>71167</td>
  <td>0.9</td>
 </tr>
</table>
sql-server-2008 disk-structures

2 respostas

  1. Best Answer

    Infelizmente, este é um grande e velho "depende". Complicado ainda mais por você ter tantos aplicativos, provavelmente com perfis IO totalmente diferentes, compartilhando a mesma instância/servidor e arrays.

    Usually you would want to isolate data and log files as the IO profiles are polar opposite. Typically weighted toward random read for data files and sequential write for logs. The log element is somewhat different in your case as you have multiple log files.

    I'd start by getting an understanding of the IO the databases are consuming relative to each other.

        SELECT
        DB_NAME(fs.database_id) AS [Database Name]
      , mf.physical_name
      , io_stall_read_ms
      , num_of_reads
      , CAST(io_stall_read_ms / (1.0 + num_of_reads) AS NUMERIC(10, 1)) AS [avg_read_stall_ms]
      , io_stall_write_ms
      , num_of_writes
      , CAST(io_stall_write_ms / (1.0 + num_of_writes) AS NUMERIC(10, 1)) AS [avg_write_stall_ms]
      , io_stall_read_ms + io_stall_write_ms AS [io_stalls]
      , num_of_reads + num_of_writes AS [total_io]
      , CAST((io_stall_read_ms + io_stall_write_ms) 
        / (1.0 + num_of_reads + num_of_writes) AS NUMERIC(10,1)) AS [avg_io_stall_ms]
    FROM
        sys.dm_io_virtual_file_stats(NULL, NULL) AS fs
    INNER JOIN sys.master_files AS mf
    ON  fs.database_id = mf.database_id
        AND fs.[file_id] = mf.[file_id]
    ORDER BY
            DatabaseName ASC, mf.physical_name
--  num_of_reads DESC
--  num_of_writes DESC  
    OPTION (RECOMPILE) ;

    If you can format the output of this into a readable form and add to your question, someone can make a more educated guess at the best use of your 18 disks.

    If I was doing this blind, I'd probably start off allocating:

    • 6 RAID10 for the busiest database's data files
    • 6 RAID10 for the other database's data files
    • 4 RAID10 shared Logs
    • 2 RAID1 Tempdb (your single disk configuration is a risky single point of failure)

    Assuming that:

    1. the SAN hosts other arrays and therefore hot spares are available from a pool
    2. snapshot isolation isn't in use or isn't placing heavy demands on tempdb

    Edit: Following update to question regarding queue lengths:

    Queue length counters are oft misunderstood when evaluating SQL Server performance. One of the best analogies I've come across is from a Simon Sabin blog post, Disk Queue Length - a bit like buying Guiness.

    In your case, they are so low that you might get by with half the spindles. Would still be interesting to see the other stats from the above query though.

    • 8

  2. First the tempdb needs to have RAID under it. When that disk fails your SQL Server will come to a stop until you replace the failed disk and get it back up and running. If no one else is using the 4 disk RAID 5 you could reconfigure that as RAID 10 and use that for the logs or the data depending on which has the lower IO needs, and leave the higher IO one on the bigger RAID set.

    This all requires a good looking at the perfmon numbers that you are getting for each disk to see which one should go where.

    • 3

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