On Thu, Jan 7, 2021 at 12:45 PM Bharath Rupireddy <bharath.rupireddyforpostg...@gmail.com> wrote: > > On Thu, Jan 7, 2021 at 11:32 AM Amul Sul <sula...@gmail.com> wrote: > > Snip from CreateCheckPoint(): > > -- > > /* > > * Acquire CheckpointLock to ensure only one checkpoint happens at a time. > > * (This is just pro forma, since in the present system structure there is > > * only one process that is allowed to issue checkpoints at any given > > * time.) > > */ > > LWLockAcquire(CheckpointLock, LW_EXCLUSIVE); > > -- > > > > As per this comment, it seems to be that we don't really need this LW lock. > > We > > could have something else instead if we are afraid of having multiple > > checkpoints at any given time which isn't possible, btw. > > Looks like CheckpointLock() can also be called in standalone backends > (RequestCheckpoint->CreateCheckPoint) along with the checkpointer > process. Having said that, I'm not quite sure whether it can get > called at the same time from a backend(may be with checkpoint; > command) and the checkpointer process.
If it is a standalone backend then there will be no postmaster and no other process i.e. no checkpoint process also. -- Regards, Dilip Kumar EnterpriseDB: http://www.enterprisedb.com
