featurebase/rbf/cfg/cfg.go
2022-09-06 09:39:22 -07:00

78 lines
3.3 KiB
Go

// Copyright 2022 Molecula Corp. (DBA FeatureBase).
// SPDX-License-Identifier: Apache-2.0
package cfg
import (
"github.com/featurebasedb/featurebase/v3/logger"
"github.com/spf13/pflag"
)
const (
DefaultMinWALCheckpointSize = 1 * (1 << 20) // 1MB
DefaultMaxWALCheckpointSize = DefaultMaxWALSize / 2
)
// Config defines externally configurable rbf options.
// The separate package avoids circular import.
type Config struct {
// The maximum allowed database size. Required by mmap.
MaxSize int64 `toml:"max-db-size"`
// The maximum allowed WAL size. Required by mmap.
MaxWALSize int64 `toml:"max-wal-size"`
// The minimum WAL size before the WAL is copied to the DB.
MinWALCheckpointSize int64 `toml:"min-wal-checkpoint-size"`
// The maximum WAL size before transactions are halted to allow a checkpoint.
MaxWALCheckpointSize int64 `toml:"max-wal-checkpoint-size"`
// Set before calling db.Open()
FsyncEnabled bool `toml:"fsync"`
FsyncWALEnabled bool `toml:"fsync-wal"`
// for mmap correctness testing.
DoAllocZero bool `toml:"do-alloc-zero"`
// CursorCacheSize is the number of copies of Cursor{} to keep in our
// readyCursorCh arena to avoid GC pressure.
CursorCacheSize int64 `toml:"cursor-cache-size"`
// Logger specifies a logger for asynchronous errors, such as
// background checkpoints. It cannot be set from toml. The default is
// to use stderr.
Logger logger.Logger `toml:"-"`
// The maximum number of bits to be deleted in a single transaction default(65536)
MaxDelete int `toml:"max-delete"`
}
func NewDefaultConfig() *Config {
return &Config{
MaxSize: DefaultMaxSize,
MaxWALSize: DefaultMaxWALSize,
MinWALCheckpointSize: DefaultMinWALCheckpointSize,
MaxWALCheckpointSize: DefaultMaxWALCheckpointSize,
FsyncEnabled: true,
FsyncWALEnabled: true,
MaxDelete: DefaultMaxDelete,
// CI passed with 20. 50 was too big for CI, even on X-large instances.
// For now we default to 0, which means use sync.Pool.
CursorCacheSize: 0,
}
}
func (cfg *Config) DefineFlags(flags *pflag.FlagSet) {
default0 := NewDefaultConfig()
flags.Int64Var(&cfg.MaxSize, "rbf.max-db-size", default0.MaxSize, "RBF maximum size in bytes of a database file (distinct from a WAL file)")
flags.Int64Var(&cfg.MaxWALSize, "rbf.max-wal-size", default0.MaxWALSize, "RBF maximum size in bytes of a WAL file (distinct from a DB file)")
flags.Int64Var(&cfg.MinWALCheckpointSize, "rbf.min-wal-checkpoint-size", default0.MinWALCheckpointSize, "RBF minimum size in bytes of a WAL file before attempting checkpoint")
flags.Int64Var(&cfg.MaxWALCheckpointSize, "rbf.max-wal-checkpoint-size", default0.MaxWALCheckpointSize, "RBF maximum size in bytes of a WAL file before forcing checkpoint")
// renamed from --rbf-fsync to just --fsync because now it applies to all Tx backends.
flags.BoolVar(&cfg.FsyncEnabled, "fsync", default0.FsyncEnabled, "enable fsync fully safe flush-to-disk")
flags.BoolVar(&cfg.FsyncWALEnabled, "fsync-wal", default0.FsyncWALEnabled, "enable fsync on write-ahead log")
flags.Int64Var(&cfg.CursorCacheSize, "rbf.cursor-cache-size", default0.CursorCacheSize, "how big a Cursor arena to maintain. 0 means use sync.Pool with dynamic sizing. Note that <= 20 is needed to pass CI. Controls the memory footprint of rbf.")
}