Re: Hiddedn blob pages

> > Hi: > > I've got a question about "blob-page-overhead". We create a blobspace > with 27,815 blob pages. The blob page is sized to hold a 128x128 image. > When asked to provide a utility for users to display the "number of > images that can be inserted into the database", I simply counted the > number of images already in the database and subtracted from the total > number of blob pages. But the users are upset because the utility is > sayingthat more images will fit in the database than can actually be > inserted.I'm now guessing that there is some per-blob overhead being > hidden thatI need to adjust for in my calculations. Is this per-blob > overhead a knownammount? > > The only other point that is bothersome is that the same application > on identical equipment will have a different maximum image count. Any > ideas?? > > Frank The probable cause of your problem is the fact that when a blob is inserted it takes up twice the amount of space until the blob is written out to the locical log archive. This is because BLOBs are not wriiten directly to the logical log, but instead two copies are held so that the before and after image can be written out later. Malcolm Weallans 0628-72154