Обсуждение: Question for the developers.
Hi, I am Suchindra Katageri and am working as a Software Engineer atLinuxlabs, Atlanta, GA.I am presently working on developinglibraries to make postgresqlrun on a cluster. I was wondering if it was possible to force Databasewrites to stablestorage, without messing up with the postgres code.e.g. force the PostgreSQL to write to stable storage after an INSERTcommand. Thanks in advance. -- regards, --suchindra
suchindra@linuxlabs.com wrote: > > Hi, > > I am Suchindra Katageri and am working as a Software Engineer at > Linuxlabs, Atlanta, GA. > > I am presently working on developing libraries to make postgresql > run on a cluster. I was wondering if it was possible to force Database > writes to stable storage, without messing up with the postgres code. > e.g. force the PostgreSQL to write to stable storage after an INSERT > command. For stable storage, you mean disk storage? You need fsync for that, probably, but we already fsync our write-ahead log (WAL) on every commit. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
suchindra@linuxlabs.com wrote: > Hi, > > I am Suchindra Katageri and am working as a Software Engineer at > Linuxlabs, Atlanta, GA. > > I am presently working on developing libraries to make postgresql > run on a cluster. I was wondering if it was possible to force Database > writes to stable storage, without messing up with the postgres code. > e.g. force the PostgreSQL to write to stable storage after an INSERT > command. I don't see how that would help you very far. PostgreSQL holds disk buffers in a shared memory cache. And unless you modify that cache, it would not read from the file again if it thinks it knows the content already. How do you intend to remove pages from that shared buffer cache at the time, another cluster member modifies the same logical page? Jan -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== JanWieck@Yahoo.com #