31 lines
1.1 KiB
Go
31 lines
1.1 KiB
Go
package helpers
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import (
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"fmt"
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)
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// BlockSizeLimit specifies the maximum size an imported block can have.
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var BlockSizeLimit = 1048576 // 1 MB
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// rough estimates on expected sizes
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var roughLinkBlockSize = 1 << 13 // 8KB
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var roughLinkSize = 34 + 8 + 5 // sha256 multihash + size + no name + protobuf framing
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// DefaultLinksPerBlock governs how the importer decides how many links there
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// will be per block. This calculation is based on expected distributions of:
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// * the expected distribution of block sizes
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// * the expected distribution of link sizes
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// * desired access speed
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// For now, we use:
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//
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// var roughLinkBlockSize = 1 << 13 // 8KB
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// var roughLinkSize = 34 + 8 + 5 // sha256 multihash + size + no name
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// // + protobuf framing
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// var DefaultLinksPerBlock = (roughLinkBlockSize / roughLinkSize)
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// = ( 8192 / 47 )
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// = (approximately) 174
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var DefaultLinksPerBlock = roughLinkBlockSize / roughLinkSize
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// ErrSizeLimitExceeded signals that a block is larger than BlockSizeLimit.
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var ErrSizeLimitExceeded = fmt.Errorf("object size limit exceeded")
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