| | 105 | === 3.1.2. Enabling "Write Cache" with arcconf === |
| | 106 | |
| | 107 | Enabling this feature can lead to major performance improvments in write mode.[[BR]] |
| | 108 | '''HOWEVER''', all data stored in cache will be lost if a power failure or a hard reboot occurs.[[BR]] |
| | 109 | So, you're supposed to keep write cache disabled if your controller doesn't have any battery pack. |
| | 110 | |
| | 111 | {{{ |
| | 112 | server:~# arcconf GETCONFIG 1 |
| | 113 | [...] |
| | 114 | Controller Battery Information |
| | 115 | -------------------------------------------------------- |
| | 116 | Status : Not Installed |
| | 117 | [...] |
| | 118 | Logical device number 0 |
| | 119 | Logical device name : RAID1 |
| | 120 | RAID level : 1 |
| | 121 | Status of logical device : Optimal |
| | 122 | Size : 953836 MB |
| | 123 | Read-cache mode : Enabled |
| | 124 | Write-cache mode : Disabled (write-through) |
| | 125 | Write-cache setting : Disabled (write-through) |
| | 126 | [...] |
| | 127 | }}} |
| | 128 | |
| | 129 | So here is current config: No battery pack on the controller, and thus, write cache disabled.[[BR]] |
| | 130 | But I want to enable it, this server doesn't store really useful data; only speed matters here... |
| | 131 | |
| | 132 | Let's enable write cache: |
| | 133 | {{{ |
| | 134 | server:~# arcconf SETCACHE 1 LOGICALDRIVE 0 wb |
| | 135 | Controllers found: 1 |
| | 136 | WARNING: Power failure without battery support will lead to data loss. |
| | 137 | Do you wish to continue? |
| | 138 | Press y, then ENTER to continue or press ENTER to abort: y |
| | 139 | |
| | 140 | |
| | 141 | Command completed successfully. |
| | 142 | }}} |
| | 143 | |
| | 144 | Here we go ! Let's check if it's really enabled, and then, reboot. |
| | 145 | {{{ |
| | 146 | server:~# arcconf GETCONFIG 1 |
| | 147 | [...] |
| | 148 | Logical device number 0 |
| | 149 | Logical device name : RAID1 |
| | 150 | RAID level : 1 |
| | 151 | Status of logical device : Optimal |
| | 152 | Size : 953836 MB |
| | 153 | Read-cache mode : Enabled |
| | 154 | Write-cache mode : Enabled (write-back) |
| | 155 | Write-cache setting : Enabled (write-back) |
| | 156 | }}} |
| | 157 | |