Tom Lane wrote: > Bruce Momjian <[EMAIL PROTECTED]> writes: > > Jim C. Nasby wrote: > >> What about the mmap/msync(?)/munmap idea someone mentioned? > > > I see that as similar to using O_DIRECT during checkpoint, which had > > poor performance. > > That's a complete nonstarter on portability grounds, even if msync gave > us the desired semantics, which it doesn't. It's no better than fsync > for our purposes. > > To my mind the problem with fsync is not that it gives us too little > control but that it gives too much: we have to specify a particular > order of writing out files. What we'd really like is a version of > sync(2) that tells us when it's done but doesn't constrain the I/O > scheduler's choices at all. Unfortunately there's no such API ...
Yea, we used to use sync() but that did all files, not just the PostgreSQL ones. -- Bruce Momjian [EMAIL PROTECTED] EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
