forked from TrueCloudLab/frostfs-node
21 lines
858 B
Go
21 lines
858 B
Go
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// Package writecache implements write-cache for objects.
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//
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// It contains in-memory cache of fixed size and underlying database
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// (usually on SSD) for storing small objects.
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// There are 3 places where object can be:
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// 1. In-memory cache.
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// 2. On-disk cache DB.
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// 3. Main storage (blobstor).
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//
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// There are 2 types of background jobs:
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// 1. Persisting objects from in-memory cache to database.
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// 2. Flushing objects from database to blobstor.
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// On flushing object address is put in in-memory LRU cache.
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// The actual deletion from the DB is done when object
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// is evicted from this cache.
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//
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// Putting objects to the main storage is done by multiple workers.
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// Some of them prioritize flushing items, others prioritize putting new objects.
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// The current ration is 50/50. This helps to make some progress even under load.
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package writecache
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