dimgigov
e1bae0c7a0
- Add docs/ folder with English (en/) and Bulgarian (bg/) documentation - Create index.md with language switching and links - English docs: installation, quickstart, architecture, baraql, storage, schema, lsm, btree, vector, graph, fts, columnar, transactions, distributed, protocol, udf, api-binary, api-http, api-websocket - Bulgarian docs: installation, quickstart, architecture, baraql, schema, lsm, btree, vector, graph, fts, transactions, distributed - Update README license to BSD 3-Clause - Add LICENSE file with BSD 3-Clause text
64 lines
2.1 KiB
Markdown
64 lines
2.1 KiB
Markdown
# LSM-Tree Storage Engine
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The primary storage engine in BaraDB using the Log-Structured Merge-Tree architecture.
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## Architecture
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```
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┌─────────────────────────────────────────────┐
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│ Writes │
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│ (append to WAL + MemTable) │
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└─────────────────────────────────────────────┘
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│
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▼
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┌─────────────────────────────────────────────┐
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│ MemTable │
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│ (in-memory sorted buffer) │
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└─────────────────────────────────────────────┘
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│
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(when full, flush to SSTable)
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│
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▼
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┌─────────────────────────────────────────────┐
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│ SSTable │
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│ (sorted string table on disk) │
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└─────────────────────────────────────────────┘
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```
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## Usage
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```nim
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import barabadb/storage/lsm
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var db = newLSMTree("./data")
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# Write
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db.put("key1", cast[seq[byte]]("value1"))
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# Read
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let (found, value) = db.get("key1")
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# Delete
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db.delete("key1")
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db.close()
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```
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## Features
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- **Write-optimized**: Append-only log structure
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- **Durability**: Write-ahead log (WAL) ensures crash recovery
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- **Bloom Filter**: Fast negative lookups
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- **Compaction**: Size-tiered strategy merges SSTables
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- **Page Cache**: LRU cache for frequently accessed pages
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## Configuration
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```nim
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var db = newLSMTree(
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path = "./data",
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memTableSize = 64 * 1024 * 1024, # 64MB
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walEnabled = true,
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bloomFpRate = 0.01
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)
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``` |