705 lines
22 KiB
Rust
705 lines
22 KiB
Rust
// Copyright 2015, 2016 Ethcore (UK) Ltd.
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// This file is part of Parity.
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// Parity is free software: you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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// Parity is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with Parity. If not, see <http://www.gnu.org/licenses/>.
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//! Key-Value store abstraction with `RocksDB` backend.
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use std::io::ErrorKind;
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use common::*;
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use elastic_array::*;
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use std::default::Default;
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use std::path::PathBuf;
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use hashdb::DBValue;
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use rlp::{UntrustedRlp, RlpType, View, Compressible};
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use rocksdb::{DB, Writable, WriteBatch, WriteOptions, IteratorMode, DBIterator,
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Options, DBCompactionStyle, BlockBasedOptions, Direction, Cache, Column, ReadOptions};
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#[cfg(target_os = "linux")]
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use regex::Regex;
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#[cfg(target_os = "linux")]
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use std::process::Command;
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#[cfg(target_os = "linux")]
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use std::fs::File;
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const DB_BACKGROUND_FLUSHES: i32 = 2;
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const DB_BACKGROUND_COMPACTIONS: i32 = 2;
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/// Write transaction. Batches a sequence of put/delete operations for efficiency.
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pub struct DBTransaction {
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ops: Vec<DBOp>,
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}
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enum DBOp {
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Insert {
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col: Option<u32>,
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key: ElasticArray32<u8>,
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value: DBValue,
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},
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InsertCompressed {
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col: Option<u32>,
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key: ElasticArray32<u8>,
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value: DBValue,
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},
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Delete {
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col: Option<u32>,
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key: ElasticArray32<u8>,
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}
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}
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impl DBTransaction {
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/// Create new transaction.
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pub fn new(_db: &Database) -> DBTransaction {
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DBTransaction {
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ops: Vec::with_capacity(256),
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}
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}
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/// Insert a key-value pair in the transaction. Any existing value value will be overwritten upon write.
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pub fn put(&mut self, col: Option<u32>, key: &[u8], value: &[u8]) {
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let mut ekey = ElasticArray32::new();
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ekey.append_slice(key);
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self.ops.push(DBOp::Insert {
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col: col,
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key: ekey,
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value: DBValue::from_slice(value),
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});
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}
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/// Insert a key-value pair in the transaction. Any existing value value will be overwritten upon write.
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pub fn put_vec(&mut self, col: Option<u32>, key: &[u8], value: Bytes) {
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let mut ekey = ElasticArray32::new();
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ekey.append_slice(key);
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self.ops.push(DBOp::Insert {
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col: col,
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key: ekey,
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value: DBValue::from_vec(value),
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});
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}
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/// Insert a key-value pair in the transaction. Any existing value value will be overwritten upon write.
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/// Value will be RLP-compressed on flush
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pub fn put_compressed(&mut self, col: Option<u32>, key: &[u8], value: Bytes) {
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let mut ekey = ElasticArray32::new();
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ekey.append_slice(key);
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self.ops.push(DBOp::InsertCompressed {
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col: col,
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key: ekey,
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value: DBValue::from_vec(value),
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});
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}
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/// Delete value by key.
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pub fn delete(&mut self, col: Option<u32>, key: &[u8]) {
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let mut ekey = ElasticArray32::new();
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ekey.append_slice(key);
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self.ops.push(DBOp::Delete {
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col: col,
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key: ekey,
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});
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}
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}
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enum KeyState {
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Insert(DBValue),
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InsertCompressed(DBValue),
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Delete,
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}
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/// Compaction profile for the database settings
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#[derive(Clone, Copy, PartialEq, Debug)]
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pub struct CompactionProfile {
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/// L0-L1 target file size
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pub initial_file_size: u64,
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/// L2-LN target file size multiplier
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pub file_size_multiplier: i32,
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/// rate limiter for background flushes and compactions, bytes/sec, if any
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pub write_rate_limit: Option<u64>,
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}
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impl Default for CompactionProfile {
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/// Default profile suitable for most storage
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fn default() -> CompactionProfile {
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CompactionProfile::ssd()
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}
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}
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/// Given output of df command return Linux rotational flag file path.
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#[cfg(target_os = "linux")]
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pub fn rotational_from_df_output(df_out: Vec<u8>) -> Option<PathBuf> {
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str::from_utf8(df_out.as_slice())
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.ok()
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// Get the drive name.
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.and_then(|df_str| Regex::new(r"/dev/(sd[:alpha:]{1,2})")
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.ok()
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.and_then(|re| re.captures(df_str))
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.and_then(|captures| captures.at(1)))
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// Generate path e.g. /sys/block/sda/queue/rotational
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.map(|drive_path| {
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let mut p = PathBuf::from("/sys/block");
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p.push(drive_path);
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p.push("queue/rotational");
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p
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})
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}
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impl CompactionProfile {
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/// Attempt to determine the best profile automatically, only Linux for now.
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#[cfg(target_os = "linux")]
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pub fn auto(db_path: &Path) -> CompactionProfile {
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let hdd_check_file = db_path
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.to_str()
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.and_then(|path_str| Command::new("df").arg(path_str).output().ok())
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.and_then(|df_res| match df_res.status.success() {
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true => Some(df_res.stdout),
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false => None,
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})
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.and_then(rotational_from_df_output);
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// Read out the file and match compaction profile.
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if let Some(hdd_check) = hdd_check_file {
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if let Ok(mut file) = File::open(hdd_check.as_path()) {
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let mut buffer = [0; 1];
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if file.read_exact(&mut buffer).is_ok() {
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// 0 means not rotational.
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if buffer == [48] { return Self::ssd(); }
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// 1 means rotational.
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if buffer == [49] { return Self::hdd(); }
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}
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}
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}
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// Fallback if drive type was not determined.
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Self::default()
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}
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/// Just default for other platforms.
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#[cfg(not(target_os = "linux"))]
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pub fn auto(_db_path: &Path) -> CompactionProfile {
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Self::default()
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}
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/// Default profile suitable for SSD storage
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pub fn ssd() -> CompactionProfile {
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CompactionProfile {
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initial_file_size: 32 * 1024 * 1024,
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file_size_multiplier: 2,
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write_rate_limit: None,
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}
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}
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/// Slow HDD compaction profile
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pub fn hdd() -> CompactionProfile {
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CompactionProfile {
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initial_file_size: 192 * 1024 * 1024,
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file_size_multiplier: 1,
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write_rate_limit: Some(8 * 1024 * 1024),
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}
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}
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}
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/// Database configuration
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#[derive(Clone)]
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pub struct DatabaseConfig {
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/// Max number of open files.
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pub max_open_files: i32,
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/// Cache sizes (in MiB) for specific columns.
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pub cache_sizes: HashMap<Option<u32>, usize>,
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/// Compaction profile
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pub compaction: CompactionProfile,
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/// Set number of columns
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pub columns: Option<u32>,
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/// Should we keep WAL enabled?
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pub wal: bool,
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}
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impl DatabaseConfig {
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/// Create new `DatabaseConfig` with default parameters and specified set of columns.
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/// Note that cache sizes must be explicitly set.
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pub fn with_columns(columns: Option<u32>) -> Self {
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let mut config = Self::default();
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config.columns = columns;
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config
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}
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/// Set the column cache size in MiB.
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pub fn set_cache(&mut self, col: Option<u32>, size: usize) {
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self.cache_sizes.insert(col, size);
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}
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}
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impl Default for DatabaseConfig {
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fn default() -> DatabaseConfig {
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DatabaseConfig {
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cache_sizes: HashMap::new(),
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max_open_files: 512,
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compaction: CompactionProfile::default(),
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columns: None,
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wal: true,
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}
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}
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}
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/// Database iterator for flushed data only
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pub struct DatabaseIterator {
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iter: DBIterator,
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}
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impl<'a> Iterator for DatabaseIterator {
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type Item = (Box<[u8]>, Box<[u8]>);
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fn next(&mut self) -> Option<Self::Item> {
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self.iter.next()
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}
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}
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struct DBAndColumns {
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db: DB,
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cfs: Vec<Column>,
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}
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/// Key-Value database.
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pub struct Database {
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db: RwLock<Option<DBAndColumns>>,
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config: DatabaseConfig,
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write_opts: WriteOptions,
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read_opts: ReadOptions,
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path: String,
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// Dirty values added with `write_buffered`. Cleaned on `flush`.
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overlay: RwLock<Vec<HashMap<ElasticArray32<u8>, KeyState>>>,
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// Values currently being flushed. Cleared when `flush` completes.
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flushing: RwLock<Vec<HashMap<ElasticArray32<u8>, KeyState>>>,
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// Prevents concurrent flushes.
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// Value indicates if a flush is in progress.
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flushing_lock: Mutex<bool>,
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}
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impl Database {
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/// Open database with default settings.
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pub fn open_default(path: &str) -> Result<Database, String> {
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Database::open(&DatabaseConfig::default(), path)
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}
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/// Open database file. Creates if it does not exist.
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pub fn open(config: &DatabaseConfig, path: &str) -> Result<Database, String> {
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// default cache size for columns not specified.
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const DEFAULT_CACHE: usize = 2;
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let mut opts = Options::new();
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if let Some(rate_limit) = config.compaction.write_rate_limit {
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try!(opts.set_parsed_options(&format!("rate_limiter_bytes_per_sec={}", rate_limit)));
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}
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try!(opts.set_parsed_options(&format!("max_total_wal_size={}", 64 * 1024 * 1024)));
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try!(opts.set_parsed_options("verify_checksums_in_compaction=0"));
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opts.set_max_open_files(config.max_open_files);
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opts.create_if_missing(true);
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opts.set_use_fsync(false);
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opts.set_max_background_flushes(DB_BACKGROUND_FLUSHES);
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opts.set_max_background_compactions(DB_BACKGROUND_COMPACTIONS);
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// compaction settings
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opts.set_compaction_style(DBCompactionStyle::DBUniversalCompaction);
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opts.set_target_file_size_base(config.compaction.initial_file_size);
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opts.set_target_file_size_multiplier(config.compaction.file_size_multiplier);
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let mut cf_options = Vec::with_capacity(config.columns.unwrap_or(0) as usize);
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let cfnames: Vec<_> = (0..config.columns.unwrap_or(0)).map(|c| format!("col{}", c)).collect();
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let cfnames: Vec<&str> = cfnames.iter().map(|n| n as &str).collect();
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for col in 0 .. config.columns.unwrap_or(0) {
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let mut opts = Options::new();
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opts.set_compaction_style(DBCompactionStyle::DBUniversalCompaction);
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opts.set_target_file_size_base(config.compaction.initial_file_size);
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opts.set_target_file_size_multiplier(config.compaction.file_size_multiplier);
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let col_opt = config.columns.map(|_| col);
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{
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let cache_size = config.cache_sizes.get(&col_opt).cloned().unwrap_or(DEFAULT_CACHE);
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let mut block_opts = BlockBasedOptions::new();
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// all goes to read cache.
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block_opts.set_cache(Cache::new(cache_size * 1024 * 1024));
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opts.set_block_based_table_factory(&block_opts);
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}
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cf_options.push(opts);
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}
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let mut write_opts = WriteOptions::new();
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if !config.wal {
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write_opts.disable_wal(true);
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}
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let mut read_opts = ReadOptions::new();
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read_opts.set_verify_checksums(false);
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let mut cfs: Vec<Column> = Vec::new();
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let db = match config.columns {
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Some(columns) => {
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match DB::open_cf(&opts, path, &cfnames, &cf_options) {
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Ok(db) => {
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cfs = cfnames.iter().map(|n| db.cf_handle(n)
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.expect("rocksdb opens a cf_handle for each cfname; qed")).collect();
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assert!(cfs.len() == columns as usize);
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Ok(db)
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}
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Err(_) => {
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// retry and create CFs
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match DB::open_cf(&opts, path, &[], &[]) {
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Ok(mut db) => {
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cfs = try!(cfnames.iter().enumerate().map(|(i, n)| db.create_cf(n, &cf_options[i])).collect());
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Ok(db)
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},
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err @ Err(_) => err,
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}
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}
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}
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},
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None => DB::open(&opts, path)
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};
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let db = match db {
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Ok(db) => db,
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Err(ref s) if s.starts_with("Corruption:") => {
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info!("{}", s);
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info!("Attempting DB repair for {}", path);
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try!(DB::repair(&opts, path));
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match cfnames.is_empty() {
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true => try!(DB::open(&opts, path)),
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false => try!(DB::open_cf(&opts, path, &cfnames, &cf_options))
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}
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},
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Err(s) => { return Err(s); }
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};
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let num_cols = cfs.len();
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Ok(Database {
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db: RwLock::new(Some(DBAndColumns{ db: db, cfs: cfs })),
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config: config.clone(),
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write_opts: write_opts,
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overlay: RwLock::new((0..(num_cols + 1)).map(|_| HashMap::new()).collect()),
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flushing: RwLock::new((0..(num_cols + 1)).map(|_| HashMap::new()).collect()),
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flushing_lock: Mutex::new((false)),
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path: path.to_owned(),
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read_opts: read_opts,
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})
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}
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/// Creates new transaction for this database.
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pub fn transaction(&self) -> DBTransaction {
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DBTransaction::new(self)
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}
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fn to_overlay_column(col: Option<u32>) -> usize {
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col.map_or(0, |c| (c + 1) as usize)
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}
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/// Commit transaction to database.
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pub fn write_buffered(&self, tr: DBTransaction) {
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let mut overlay = self.overlay.write();
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let ops = tr.ops;
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for op in ops {
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match op {
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DBOp::Insert { col, key, value } => {
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let c = Self::to_overlay_column(col);
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overlay[c].insert(key, KeyState::Insert(value));
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},
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DBOp::InsertCompressed { col, key, value } => {
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let c = Self::to_overlay_column(col);
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overlay[c].insert(key, KeyState::InsertCompressed(value));
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},
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DBOp::Delete { col, key } => {
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let c = Self::to_overlay_column(col);
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overlay[c].insert(key, KeyState::Delete);
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},
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}
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};
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}
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/// Commit buffered changes to database. Must be called under `flush_lock`
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fn write_flushing_with_lock(&self, _lock: &mut MutexGuard<bool>) -> Result<(), String> {
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match *self.db.read() {
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Some(DBAndColumns { ref db, ref cfs }) => {
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let batch = WriteBatch::new();
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mem::swap(&mut *self.overlay.write(), &mut *self.flushing.write());
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{
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for (c, column) in self.flushing.read().iter().enumerate() {
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for (ref key, ref state) in column.iter() {
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match **state {
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KeyState::Delete => {
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if c > 0 {
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try!(batch.delete_cf(cfs[c - 1], &key));
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} else {
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try!(batch.delete(&key));
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}
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},
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KeyState::Insert(ref value) => {
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if c > 0 {
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try!(batch.put_cf(cfs[c - 1], &key, value));
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} else {
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try!(batch.put(&key, &value));
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}
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},
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KeyState::InsertCompressed(ref value) => {
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let compressed = UntrustedRlp::new(&value).compress(RlpType::Blocks);
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if c > 0 {
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try!(batch.put_cf(cfs[c - 1], &key, &compressed));
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} else {
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try!(batch.put(&key, &value));
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}
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}
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}
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}
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}
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}
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try!(db.write_opt(batch, &self.write_opts));
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for column in self.flushing.write().iter_mut() {
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column.clear();
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}
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Ok(())
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},
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None => Err("Database is closed".to_owned())
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}
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}
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/// Commit buffered changes to database.
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pub fn flush(&self) -> Result<(), String> {
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let mut lock = self.flushing_lock.lock();
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// If RocksDB batch allocation fails the thread gets terminated and the lock is released.
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// The value inside the lock is used to detect that.
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if *lock {
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// This can only happen if another flushing thread is terminated unexpectedly.
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return Err("Database write failure. Running low on memory perhaps?".to_owned());
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}
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*lock = true;
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let result = self.write_flushing_with_lock(&mut lock);
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*lock = false;
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result
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}
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/// Commit transaction to database.
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pub fn write(&self, tr: DBTransaction) -> Result<(), String> {
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match *self.db.read() {
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Some(DBAndColumns { ref db, ref cfs }) => {
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let batch = WriteBatch::new();
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let ops = tr.ops;
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for op in ops {
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match op {
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DBOp::Insert { col, key, value } => {
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try!(col.map_or_else(|| batch.put(&key, &value), |c| batch.put_cf(cfs[c as usize], &key, &value)))
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},
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DBOp::InsertCompressed { col, key, value } => {
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let compressed = UntrustedRlp::new(&value).compress(RlpType::Blocks);
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try!(col.map_or_else(|| batch.put(&key, &compressed), |c| batch.put_cf(cfs[c as usize], &key, &compressed)))
|
|
},
|
|
DBOp::Delete { col, key } => {
|
|
try!(col.map_or_else(|| batch.delete(&key), |c| batch.delete_cf(cfs[c as usize], &key)))
|
|
},
|
|
}
|
|
}
|
|
db.write_opt(batch, &self.write_opts)
|
|
},
|
|
None => Err("Database is closed".to_owned())
|
|
}
|
|
}
|
|
|
|
/// Get value by key.
|
|
pub fn get(&self, col: Option<u32>, key: &[u8]) -> Result<Option<DBValue>, String> {
|
|
match *self.db.read() {
|
|
Some(DBAndColumns { ref db, ref cfs }) => {
|
|
let overlay = &self.overlay.read()[Self::to_overlay_column(col)];
|
|
match overlay.get(key) {
|
|
Some(&KeyState::Insert(ref value)) | Some(&KeyState::InsertCompressed(ref value)) => Ok(Some(value.clone())),
|
|
Some(&KeyState::Delete) => Ok(None),
|
|
None => {
|
|
let flushing = &self.flushing.read()[Self::to_overlay_column(col)];
|
|
match flushing.get(key) {
|
|
Some(&KeyState::Insert(ref value)) | Some(&KeyState::InsertCompressed(ref value)) => Ok(Some(value.clone())),
|
|
Some(&KeyState::Delete) => Ok(None),
|
|
None => {
|
|
col.map_or_else(
|
|
|| db.get_opt(key, &self.read_opts).map(|r| r.map(|v| DBValue::from_slice(&v))),
|
|
|c| db.get_cf_opt(cfs[c as usize], key, &self.read_opts).map(|r| r.map(|v| DBValue::from_slice(&v))))
|
|
},
|
|
}
|
|
},
|
|
}
|
|
},
|
|
None => Ok(None),
|
|
}
|
|
}
|
|
|
|
/// Get value by partial key. Prefix size should match configured prefix size. Only searches flushed values.
|
|
// TODO: support prefix seek for unflushed data
|
|
pub fn get_by_prefix(&self, col: Option<u32>, prefix: &[u8]) -> Option<Box<[u8]>> {
|
|
match *self.db.read() {
|
|
Some(DBAndColumns { ref db, ref cfs }) => {
|
|
let mut iter = col.map_or_else(|| db.iterator_opt(IteratorMode::From(prefix, Direction::Forward), &self.read_opts),
|
|
|c| db.iterator_cf_opt(cfs[c as usize], IteratorMode::From(prefix, Direction::Forward), &self.read_opts)
|
|
.expect("iterator params are valid; qed"));
|
|
match iter.next() {
|
|
// TODO: use prefix_same_as_start read option (not availabele in C API currently)
|
|
Some((k, v)) => if k[0 .. prefix.len()] == prefix[..] { Some(v) } else { None },
|
|
_ => None
|
|
}
|
|
},
|
|
None => None,
|
|
}
|
|
}
|
|
|
|
/// Get database iterator for flushed data.
|
|
pub fn iter(&self, col: Option<u32>) -> DatabaseIterator {
|
|
//TODO: iterate over overlay
|
|
match *self.db.read() {
|
|
Some(DBAndColumns { ref db, ref cfs }) => {
|
|
col.map_or_else(|| DatabaseIterator { iter: db.iterator_opt(IteratorMode::Start, &self.read_opts) },
|
|
|c| DatabaseIterator { iter: db.iterator_cf_opt(cfs[c as usize], IteratorMode::Start, &self.read_opts)
|
|
.expect("iterator params are valid; qed") })
|
|
},
|
|
None => panic!("Not supported yet") //TODO: return an empty iterator or change return type
|
|
}
|
|
}
|
|
|
|
/// Close the database
|
|
fn close(&self) {
|
|
*self.db.write() = None;
|
|
self.overlay.write().clear();
|
|
self.flushing.write().clear();
|
|
}
|
|
|
|
/// Restore the database from a copy at given path.
|
|
pub fn restore(&self, new_db: &str) -> Result<(), UtilError> {
|
|
self.close();
|
|
|
|
let mut backup_db = PathBuf::from(&self.path);
|
|
backup_db.pop();
|
|
backup_db.push("backup_db");
|
|
|
|
let existed = match fs::rename(&self.path, &backup_db) {
|
|
Ok(_) => true,
|
|
Err(e) => if let ErrorKind::NotFound = e.kind() {
|
|
false
|
|
} else {
|
|
return Err(e.into());
|
|
}
|
|
};
|
|
|
|
match fs::rename(&new_db, &self.path) {
|
|
Ok(_) => {
|
|
// clean up the backup.
|
|
if existed {
|
|
try!(fs::remove_dir_all(&backup_db));
|
|
}
|
|
}
|
|
Err(e) => {
|
|
// restore the backup.
|
|
if existed {
|
|
try!(fs::rename(&backup_db, &self.path));
|
|
}
|
|
return Err(e.into())
|
|
}
|
|
}
|
|
|
|
// reopen the database and steal handles into self
|
|
let db = try!(Self::open(&self.config, &self.path));
|
|
*self.db.write() = mem::replace(&mut *db.db.write(), None);
|
|
*self.overlay.write() = mem::replace(&mut *db.overlay.write(), Vec::new());
|
|
*self.flushing.write() = mem::replace(&mut *db.flushing.write(), Vec::new());
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
impl Drop for Database {
|
|
fn drop(&mut self) {
|
|
// write all buffered changes if we can.
|
|
let _ = self.flush();
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use hash::*;
|
|
use super::*;
|
|
use devtools::*;
|
|
use std::str::FromStr;
|
|
|
|
fn test_db(config: &DatabaseConfig) {
|
|
let path = RandomTempPath::create_dir();
|
|
let db = Database::open(config, path.as_path().to_str().unwrap()).unwrap();
|
|
let key1 = H256::from_str("02c69be41d0b7e40352fc85be1cd65eb03d40ef8427a0ca4596b1ead9a00e9fc").unwrap();
|
|
let key2 = H256::from_str("03c69be41d0b7e40352fc85be1cd65eb03d40ef8427a0ca4596b1ead9a00e9fc").unwrap();
|
|
let key3 = H256::from_str("01c69be41d0b7e40352fc85be1cd65eb03d40ef8427a0ca4596b1ead9a00e9fc").unwrap();
|
|
|
|
let mut batch = db.transaction();
|
|
batch.put(None, &key1, b"cat");
|
|
batch.put(None, &key2, b"dog");
|
|
db.write(batch).unwrap();
|
|
|
|
assert_eq!(&*db.get(None, &key1).unwrap().unwrap(), b"cat");
|
|
|
|
let contents: Vec<_> = db.iter(None).collect();
|
|
assert_eq!(contents.len(), 2);
|
|
assert_eq!(&*contents[0].0, &*key1);
|
|
assert_eq!(&*contents[0].1, b"cat");
|
|
assert_eq!(&*contents[1].0, &*key2);
|
|
assert_eq!(&*contents[1].1, b"dog");
|
|
|
|
let mut batch = db.transaction();
|
|
batch.delete(None, &key1);
|
|
db.write(batch).unwrap();
|
|
|
|
assert!(db.get(None, &key1).unwrap().is_none());
|
|
|
|
let mut batch = db.transaction();
|
|
batch.put(None, &key1, b"cat");
|
|
db.write(batch).unwrap();
|
|
|
|
let mut transaction = db.transaction();
|
|
transaction.put(None, &key3, b"elephant");
|
|
transaction.delete(None, &key1);
|
|
db.write(transaction).unwrap();
|
|
assert!(db.get(None, &key1).unwrap().is_none());
|
|
assert_eq!(&*db.get(None, &key3).unwrap().unwrap(), b"elephant");
|
|
|
|
assert_eq!(&*db.get_by_prefix(None, &key3).unwrap(), b"elephant");
|
|
assert_eq!(&*db.get_by_prefix(None, &key2).unwrap(), b"dog");
|
|
|
|
let mut transaction = db.transaction();
|
|
transaction.put(None, &key1, b"horse");
|
|
transaction.delete(None, &key3);
|
|
db.write_buffered(transaction);
|
|
assert!(db.get(None, &key3).unwrap().is_none());
|
|
assert_eq!(&*db.get(None, &key1).unwrap().unwrap(), b"horse");
|
|
|
|
db.flush().unwrap();
|
|
assert!(db.get(None, &key3).unwrap().is_none());
|
|
assert_eq!(&*db.get(None, &key1).unwrap().unwrap(), b"horse");
|
|
}
|
|
|
|
#[test]
|
|
fn kvdb() {
|
|
let path = RandomTempPath::create_dir();
|
|
let _ = Database::open_default(path.as_path().to_str().unwrap()).unwrap();
|
|
test_db(&DatabaseConfig::default());
|
|
}
|
|
|
|
#[test]
|
|
#[cfg(target_os = "linux")]
|
|
fn df_to_rotational() {
|
|
use std::path::PathBuf;
|
|
// Example df output.
|
|
let example_df = vec![70, 105, 108, 101, 115, 121, 115, 116, 101, 109, 32, 32, 32, 32, 32, 49, 75, 45, 98, 108, 111, 99, 107, 115, 32, 32, 32, 32, 32, 85, 115, 101, 100, 32, 65, 118, 97, 105, 108, 97, 98, 108, 101, 32, 85, 115, 101, 37, 32, 77, 111, 117, 110, 116, 101, 100, 32, 111, 110, 10, 47, 100, 101, 118, 47, 115, 100, 97, 49, 32, 32, 32, 32, 32, 32, 32, 54, 49, 52, 48, 57, 51, 48, 48, 32, 51, 56, 56, 50, 50, 50, 51, 54, 32, 32, 49, 57, 52, 52, 52, 54, 49, 54, 32, 32, 54, 55, 37, 32, 47, 10];
|
|
let expected_output = Some(PathBuf::from("/sys/block/sda/queue/rotational"));
|
|
assert_eq!(rotational_from_df_output(example_df), expected_output);
|
|
}
|
|
}
|