On Tue, Nov 23, 2021 at 4:31 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > "Bossart, Nathan" <bossa...@amazon.com> writes: > > I periodically hear rumblings about this behavior as well. At the > > very least, it certainly ought to be documented if it isn't yet. I > > wouldn't mind trying my hand at that. Perhaps we could also add a new > > configuration parameter if users really want to take the performance > > hit. > > A sequence's cache length is already configurable, no? > > We can hit this issue even cache=1. And even if we added the XLogFlush, with _cachesize=1_, the Xlog is still recorded/flushed every 32 values.
I know your opinion about this at [1], IIUC you probably miss the SEQ_LOG_VALS design, it was designed for the performance reason to avoid frequent xlog updates already. But after that, the XLogSync is still not called which caused this issue. [1] https://www.postgresql.org/message-id/19521.1588183354%40sss.pgh.pa.us -- Best Regards Andy Fan
