Kris Jurka wrote: > > > On Fri, 1 Jun 2007, Bruce Momjian wrote: > > > Log Message: > > ----------- > > TODO item not needed anymore now that the buffer cache is > > scan-resistant: > > > > < > > < * Allow free-behind capability for large sequential scans, perhaps using > > < posix_fadvise() > > < > > < Posix_fadvise() can control both sequential/random file caching and > > < free-behind behavior, but it is unclear how the setting affects other > > < backends that also have the file open, and the feature is not supported > > < on all operating systems. > > > > This todo item is about telling the OS cache that we don't want these > buffers kept around, not about pg's own buffer cache. So I think it's > still valid.
Agreed, re-added, and clarified it is for the kernel cache: * Allow free-behind capability for large sequential scans to avoid kernel cache spoiling Posix_fadvise() can control both sequential/random file caching and free-behind behavior, but it is unclear how the setting affects other backends that also have the file open, and the feature is not supported on all operating systems. -- Bruce Momjian <[EMAIL PROTECTED]> http://momjian.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
