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66 lines
1.2 KiB
Markdown
66 lines
1.2 KiB
Markdown
5 years ago
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# memory-pager
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Access memory using small fixed sized buffers instead of allocating a huge buffer.
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Useful if you are implementing sparse data structures (such as large bitfield).
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```
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npm install memory-pager
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```
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## Usage
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``` js
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var pager = require('paged-memory')
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var pages = pager(1024) // use 1kb per page
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var page = pages.get(10) // get page #10
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console.log(page.offset) // 10240
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console.log(page.buffer) // a blank 1kb buffer
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```
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## API
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#### `var pages = pager(pageSize)`
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Create a new pager. `pageSize` defaults to `1024`.
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#### `var page = pages.get(pageNumber, [noAllocate])`
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Get a page. The page will be allocated at first access.
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Optionally you can set the `noAllocate` flag which will make the
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method return undefined if no page has been allocated already
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A page looks like this
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``` js
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{
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offset: byteOffset,
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buffer: bufferWithPageSize
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}
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```
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#### `pages.set(pageNumber, buffer)`
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Explicitly set the buffer for a page.
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#### `pages.updated(page)`
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Mark a page as updated.
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#### `pages.lastUpdate()`
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Get the last page that was updated.
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#### `var buf = pages.toBuffer()`
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Concat all pages allocated pages into a single buffer
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## License
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MIT
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