On Nov 23, 2006, at 8:37 AM, Sefer Tov wrote:
oddities. Clearly the caching algorithm favors caching the indices to data (since they are more frequently accessed) but there is another case where *recently written* entries are often requested shortly after and I am not sure that they get prioritized correctly by the cache. My question is whether the cache algorithm caches only READ pages or also WRITTEN pages? If it does, is there to set some prioritization ratio for these per table? It would enable to tune the caching for everyone specific needs (if needed).
Any writes to a page happen via shared_buffers, so yes, writes are cached. Once a page is dirtied, it will stay that way until it's written out by the background writer, or a checkpoint writes it out. I believe that the buffer management algorithms can decide that page should be removed from the buffer, which would also write it out.
-- Jim Nasby jim@xxxxxxxxx EnterpriseDB http://enterprisedb.com 512.569.9461 (cell)
