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Use the transactor interface in metadata

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The boltdb instance in metadata is only used for getting transactions
and can also be overriden via the context to have a wider control of the
transaction boundary. Using the transactor interface allows callers of
metadata to have more control of the transaction lifecycle.

Since boltdb must be fsync'ed on commit, operations which perform many
database operations can be costly and slow. While providing transactor
via context can be used to group together operations, it does not
provide a way to manage the commit fsyncs more globally.

Signed-off-by: Derek McGowan <derek@mcg.dev>
This commit is contained in:
Derek McGowan
2024-06-25 07:12:30 -07:00
parent 741c4bde51
commit 8f9607eed5
3 changed files with 16 additions and 13 deletions
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7
core/metadata/bolt.go
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@@ -33,14 +33,15 @@ func WithTransactionContext(ctx context.Context, tx *bolt.Tx) context.Context {
return context.WithValue(ctx, transactionKey{}, tx)
}
type transactor interface {
// Transactor is the database interface for running transactions
type Transactor interface {
View(fn func(*bolt.Tx) error) error
Update(fn func(*bolt.Tx) error) error
}
// view gets a bolt db transaction either from the context
// or starts a new one with the provided bolt database.
func view(ctx context.Context, db transactor, fn func(*bolt.Tx) error) error {
func view(ctx context.Context, db Transactor, fn func(*bolt.Tx) error) error {
tx, ok := ctx.Value(transactionKey{}).(*bolt.Tx)
if !ok {
return db.View(fn)
@@ -50,7 +51,7 @@ func view(ctx context.Context, db transactor, fn func(*bolt.Tx) error) error {
// update gets a writable bolt db transaction either from the context
// or starts a new one with the provided bolt database.
func update(ctx context.Context, db transactor, fn func(*bolt.Tx) error) error {
func update(ctx context.Context, db Transactor, fn func(*bolt.Tx) error) error {
tx, ok := ctx.Value(transactionKey{}).(*bolt.Tx)
if !ok {
return db.Update(fn)