featurebase/rbf/cfg/cfg.go
2021-01-20 22:05:38 -06:00

77 lines
3.2 KiB
Go

// Copyright 2017 Pilosa Corp.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package cfg
import (
"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"`
// 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"`
}
func NewDefaultConfig() *Config {
return &Config{
MaxSize: DefaultMaxSize,
MaxWALSize: DefaultMaxWALSize,
MinWALCheckpointSize: DefaultMinWALCheckpointSize,
MaxWALCheckpointSize: DefaultMaxWALCheckpointSize,
FsyncEnabled: true,
// 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.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.")
}