Gregory Stark wrote: > > Actually no. A while back I did experiments to see how fast reading a file > sequentially was compared to reading the same file sequentially but skipping > x% of the blocks randomly. The results were surprising (to me) and depressing. > The breakeven point was about 7%. [...] > > The theory online was that as long as you're reading one page from each disk > track you're going to pay the same seek overhead as reading the entire track.
Could one take advantage of this observation in designing the DSM? Instead of a separate bit representing every page, having each bit represent 20 or so pages might be a more useful unit. It sounds like the time spent reading would be similar; while the bitmap would be significantly smaller. ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
