Changing RAID Parameters
To improve the system performance under the workload, try decreasing initialization, reconstruction, or restriping priorities.
See recommendations on configuring RAID parameters in the chapter RAID and System Setup Recommendations.
To change the RAID dynamic parameters, run:
# xicli raid modify <arg> [optional_args]|
Required argument |
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-n |
--name |
The name of the RAID. The maximum RAID name length is 28 charaters. |
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Optional arguments |
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| -am | --adaptive_merge | Except RAIDs 0, 1, 10. Enable (1) or disable (0) the Adaptive Merge write function. |
| --single_run |
Except RAIDs 0, 1, 10. Use this parameter to adjust the Adaptive Merge values once at startup. After that, the values are set and do not change at system reboot. The Adaptive Merge write function is then turned off. Does not take any value. Can only be used with the adaptive_merge parameter. |
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| -ca | --cpu_allowed |
Change the CPUs on which the RAID will be allowed to run. Possible values: a comma-separated list of CPUs, a range of CPUs indicated by a hyphen, or the value 'all' (the RAID will run on all available CPUs). The default: all. |
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-inp |
--init_prio |
Except RAID 0. Initialization priority in %. Possible values are from 0 to 100 (maximum rate of initialization). The default: 100. |
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-mwe |
--merge_write_enabled |
Except RAIDs 0, 1, 10. Enable (1) or disable (0) the Merge function for write operations. The default: 0. |
| -mre | --merge_read_enabled |
Except RAIDs 0, 1, 10. Enable (1) or disable (0) the Merge function for read operations. The default: 0. |
| -mrm | --merge_read_max |
Except RAIDs 0, 1, 10. Maximum wait time (in microseconds) for stripe accumulation with the Merge function enabled for read requests. Possible values: integers from 1 to 100000. The default: 1000. |
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-mrw |
--merge_read_wait |
Except RAIDs 0, 1, 10. Wait time (in microseconds) between read requests with the Merge function enabled. Possible values: integers from 1 to 100000. The default: 300. |
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-mwm |
--merge_write_max |
Except RAIDs 0, 1, 10. Maximum wait time (in microseconds) for stripe accumulation with the Merge function enabled for write requests. Possible values: integers from 1 to 100000. The default: 1000. |
| -mww | --merge_write_wait |
Except RAIDs 0, 1, 10. Wait time (in microseconds) between write requests with the Merge function enabled. Possible values: integers from 1 to 100000. The default: 300. |
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-ml |
--memory_limit |
RAM usage limit in MiB. Possible values: 0 and integers from 1024 to 1048576. The 0 value sets unlimited RAM usage. The default: 0 (unlimited). |
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-rcp |
--recon_prio |
Except RAID 0. Reconstruction priority in %. Possible values: from 0 to 100 (maximum rate of reconstruction). The default: 100. |
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-re |
--resync_enabled |
Except RAIDs 0, 1, 10. Enable (1) or disable (0) the resync function. The default: 1. |
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-rl |
--request_limit |
Number of simultaneous I/O requests on RAID. Possible values: integers from 0 to 4294967295. The 0 value disables the restriction. The default: 0. |
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-rsp |
--restripe_prio |
Restriping priority in %. Possible values are from 0 to 100 (maximum rate of restriping). The default: 100. |
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-se |
--sched_enabled |
Enable (1) or disable (0) the scheduling function. The default: 0. |
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-sp |
--sparepool |
Name of the spare pool to assign to the RAID. The null value removes the spare pool from the RAID. Spare pool can not be assigned to RAID 0. |
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--force_online |
Change RAID state to online if the RAID has unrecoverable sections. I/O operations on unrecoverable sections may lead to data corruption. The argument takes no value. |
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--force_resync |
Except RAIDs 0, 1, 10. Force RAID re-initialization. The argument takes no value. |
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Example: Setting reconstruction priority for the RAID ”media5” equal to 50%:
# xicli raid modify -n media5 -rcp 50