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man lvmcache: include chunk size
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@ -301,6 +301,35 @@ defines the default cache policy.
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defines the default cache settings.
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.SS Chunk size
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\&
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The size of data blocks managed by a cache pool can be specified with the
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\-\-chunksize option when the cache LV is created. The default unit
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is KiB. The value must be a multiple of 32KiB between 32KiB and 1GiB.
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Using a chunk size that is too large can result in wasteful use of the
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cache, where small reads and writes can cause large sections of an LV to
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be mapped into the cache. However, choosing a chunk size that is too
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small can result in more overhead trying to manage the numerous chunks
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that become mapped into the cache. Overhead can include both excessive
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CPU time searching for chunks, and excessive memory tracking chunks.
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Command to display the cache pool LV chunk size:
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.br
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.B lvs \-o+chunksize VG/CacheLV
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.BR lvm.conf (5)
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.B cache_pool_chunk_size
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.br
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controls the default chunk size used when creating a cache LV.
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The default value is shown by:
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.br
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.B lvmconfig \-\-type default allocation/cache_pool_chunk_size
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.SS Spare metadata LV
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\&
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