68 lines
2.6 KiB
Plaintext
68 lines
2.6 KiB
Plaintext
---
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group: disable_cleaner
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---
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Disabling cleaner is a feature that is intented to be used with read cache
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(Write-Thourgh and Write-Around modes), where no dirty data is produced, so
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the cleaning is not necessary. Its major benefit is metadata memory footprint
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reduction, which is result of not allocating "cleaning" metatada section,
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that constitutes about 20% of total metadata capacity.
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While it is possible to use disable_cleaner option Write-Back and Write-Only
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modes, it may result in performance degradation due to necessity to perform
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cleaning on eviction.
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title: Setting cleaner_disabled mode
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id: set_cleaner_disabled
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---
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It shall be possible to select cleaner_disabled mode during cache attach
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operation by setting apropirate field in attach config.
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title: Loading cache cleaner_disabled mode
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id: load_cleaner_disabled
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---
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The cleaner_disabled setting should be preserved in cache metadata, i.e. on the
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cache load/recovery the setting should be restored to the value it had before
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the cache stop.
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title: Metadata "cleaning" section allocation
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id: cleaning_section_alocation
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---
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When disable_cleaner option is selected the "cleaning" section in OCF metadata
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shall not be allocated neither in DRAM nor on the cache drive.
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title: Starting with NOP cleaning policy
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id: starting_with_nop_policy
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---
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When attaching/loading cache with disable_cleaner option selected, the cleaning
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policy shall always be NOP.
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title: NOP cleaning policy enforcement
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id: nop_enforcement
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---
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When disable_cleaner option is selected it shall not be possible to change the
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cleaning policy to other than NOP.
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title: Default setting
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id: default_setting
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---
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By default the disable_cleaner option shall not be selected.
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