Bonjour Michaël,
- double-write buffers use a pre-decided numbers of pages (32 for the
checkpointer, 128 divided into 4 buckets for the backends), which are
synced into disk once each batch is full.
- The double-write file of the checkpointer uses ordering of pages using
blocks number and files to minimize the number of syncs to happen, using
a custom sequential I/O algorithm.
I'm not sure from reading the descriptions.
Are these particular features related/similar to 9cd00c4 "Checkpoint
sorting and balancing" and 428b1d6 "Allow to trigger kernel writeback
after a configurable number of writes", committed in February 2016?
--
Fabien.
