[Tarantool-patches] [PATCH 1/1] txn_limbo: don't duplicate confirmations in WAL

[Cyrill Gorcunov]

On Wed, Jul 29, 2020 at 01:17:27AM +0200, Vladislav Shpilevoy wrote:
> When an ACK was received for an already confirmed transaction
> whose CONFIRM WAL write is in progress, it produced a second
> CONFIRM in WAL with the same LSN.
> 
> That was unnecessary work taking time and disk space for WAL
> records. Although it didn't lead to any bugs. Just was very
> inefficient.
> 
> This patch makes confirmation LSN monotonically grow. In case more
> ACKs are received for an already confirmed LSN, its confirmation
> is not written second time.
> 
> Closes #5144
Ack