At Wed, 22 Apr 2020 11:51:42 +0900, Fujii Masao <masao.fu...@oss.nttdata.com> wrote in > > I meant that we always have EOR at the end of recovery. So in the > > missing latest checkpoint (and crash recovery) case, we insert EOR > > after the immediate checkpoint. That also means we no longer set > > CHECKPOINT_END_OF_RECOVERY to the checkpoint, too. > > Could you tell me what the benefit by this change is? Even with this > change, > the server still needs to wait for the checkpoint to complete before > becoming the master and starting the service, unlike fast > promotion. No?
There's no benefit of performance. It's just for simplicity by signalling end-of-recovery in a unified way. Long ago, we had only non-fast promotion, which is marked by CHECKPOINT_END_OF_RECOVERY. When we introduced fast-promotion, it is marked by the END_OF_RECOVERY record since checkpoint record is not inserted at the promotion time. However, we internally fall back to non-fast promotion when we need to make a checkpoint immediately. If we remove non-fast checkpoint, we don't need two means to signal end-of-recovery. regards. -- Kyotaro Horiguchi NTT Open Source Software Center
