On Fri, Jun 15, 2018 at 12:16 AM, Stephen Frost <sfr...@snowman.net> wrote: > >> I have tested wal_prefetch at two powerful servers with 24 cores, 3Tb NVME >> RAID 10 storage device and 256Gb of RAM connected using InfiniBand. >> The speed of synchronous replication between two nodes is increased from 56k >> TPS to 60k TPS (on pgbench with scale 1000). > > I'm also surprised that it wasn't a larger improvement. > > Seems like it would make sense to implement in core using > posix_fadvise(), perhaps in the wal receiver and in RestoreArchivedFile > or nearby.. At least, that's the thinking I had when I was chatting w/ > Sean. >
Doing in-core certainly has some advantage such as it can easily reuse the existing xlog code rather trying to make a copy as is currently done in the patch, but I think it also depends on whether this is really a win in a number of common cases or is it just a win in some limited cases. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
