Coherence 3.3 User Guide : backup-storage

backup-storage

Description

The backup-storage element specifies the type and configuration of backup storage for a partitioned cache.

Elements

The following table describes the elements you can define within the backup-storage element.

Element	Required/Optional	Description
`<type>`	Required	Specifies the type of the storage used to hold the backup data. Legal values are: `on-heap` - The corresponding implementations class is `java.util.HashMap`. `off-heap` - The corresponding implementations class is `com.tangosol.io.nio.BinaryMap` using the `com.tangosol.io.nio.DirectBufferManager`. `file-mapped` - The corresponding implementations class is `com.tangosol.io.nio.BinaryMap` using the `com.tangosol.io.nio.MappedBufferManager`. `custom` - The corresponding implementations class is the class specified by the `class-name` element. `scheme` - The corresponding implementations class is specified as a `caching-scheme` by the `scheme-name` element. Default value is the value specified in the `tangosol-coherence.xml` descriptor.
`<initial-size>`	Optional	Only applicable with the `off-heap` and `file-mapped` types. Specifies the initial buffer size in bytes. The value of this element must be in the following format: [\d]+[[.][\d]]?[K\|k\|M\|m\|G\|g]?[B\|b]? where the first non-digit (from left to right) indicates the factor with which the preceding decimal value should be multiplied: `K` or `k` (kilo, 2¹⁰) `M` or `m` (mega, 2²⁰) `G` or `g` (giga, 2³⁰) If the value does not contain a factor, a factor of mega is assumed. Legal values are positive integers between `1` and `Integer.MAX_VALUE - 1023` (that is, 2,147,482,624 bytes). Default value is the value specified in the `tangosol-coherence.xml` descriptor.
`<maximum-size>`	Optional	Only applicable with the `off-heap` and `file-mapped` types. Specifies the initial buffer size in bytes. The value of this element must be in the following format: [\d]+[[.][\d]]?[K\|k\|M\|m\|G\|g]?[B\|b]? where the first non-digit (from left to right) indicates the factor with which the preceding decimal value should be multiplied: `K` or `k` (kilo, 2¹⁰) `M` or `m` (mega, 2²⁰) `G` or `g` (giga, 2³⁰) If the value does not contain a factor, a factor of mega is assumed. Legal values are positive integers between `1` and `Integer.MAX_VALUE - 1023` (that is, 2,147,482,624 bytes). Default value is the value specified in the `tangosol-coherence.xml` descriptor.
`<directory>`	Optional	Only applicable with the `file-mapped` type. Specifies the pathname for the directory that the disk persistence manager ( `com.tangosol.util.nio.MappedBufferManager`) will use as "root" to store files in. If not specified or specifies a non-existent directory, a temporary file in the default location is used. Default value is the value specified in the `tangosol-coherence.xml` descriptor.
`<class-name>`	Optional	Only applicable with the `custom` type. Specifies a class name for the custom storage implementation. If the class implements `com.tangosol.run.xml.XmlConfigurable` interface then upon construction the `setConfig` method is called passing the entire `backup-storage` element. Default value is the value specified in the `tangosol-coherence.xml` descriptor.
`<scheme-name>`	Optional	Only applicable with the `scheme` type. Specifies a scheme name for the `ConfigurableCacheFactory`. Default value is the value specified in the `tangosol-coherence.xml` descriptor.

Element

Required/Optional

Description

<type>

Required

Specifies the type of the storage used to hold the backup data.

Legal values are:

on-heap - The corresponding implementations class is java.util.HashMap.
off-heap - The corresponding implementations class is com.tangosol.io.nio.BinaryMap using the com.tangosol.io.nio.DirectBufferManager.
file-mapped - The corresponding implementations class is com.tangosol.io.nio.BinaryMap using the com.tangosol.io.nio.MappedBufferManager.
custom - The corresponding implementations class is the class specified by the class-name element.
scheme - The corresponding implementations class is specified as a caching-scheme by the scheme-name element.

Default value is the value specified in the tangosol-coherence.xml descriptor.

<initial-size>

Optional

Only applicable with the off-heap and file-mapped types.
Specifies the initial buffer size in bytes.

The value of this element must be in the following format:

[\d]+[[.][\d]]?[K|k|M|m|G|g]?[B|b]?

where the first non-digit (from left to right) indicates the factor with which the preceding decimal value should be multiplied:

K or k (kilo, 2¹⁰)
M or m (mega, 2²⁰)
G or g (giga, 2³⁰)

If the value does not contain a factor, a factor of mega is assumed.

Legal values are positive integers between 1 and Integer.MAX_VALUE - 1023 (that is, 2,147,482,624 bytes).

Default value is the value specified in the tangosol-coherence.xml descriptor.

<maximum-size>

Optional

Only applicable with the off-heap and file-mapped types.
Specifies the initial buffer size in bytes.

The value of this element must be in the following format:

[\d]+[[.][\d]]?[K|k|M|m|G|g]?[B|b]?

where the first non-digit (from left to right) indicates the factor with which the preceding decimal value should be multiplied:

K or k (kilo, 2¹⁰)
M or m (mega, 2²⁰)
G or g (giga, 2³⁰)

<directory>

Optional

Only applicable with the file-mapped type.

Specifies the pathname for the directory that the disk persistence manager ( com.tangosol.util.nio.MappedBufferManager) will use as "root" to store files in. If not specified or specifies a non-existent directory, a temporary file in the default location is used.

Default value is the value specified in the tangosol-coherence.xml descriptor.

<class-name>

Optional

Only applicable with the custom type.

Specifies a class name for the custom storage implementation. If the class implements com.tangosol.run.xml.XmlConfigurable interface then upon construction the setConfig method is called passing the entire backup-storage element.

Default value is the value specified in the tangosol-coherence.xml descriptor.

<scheme-name>

Optional

Only applicable with the scheme type.

Specifies a scheme name for the ConfigurableCacheFactory.

Default value is the value specified in the tangosol-coherence.xml descriptor.