Re: Why the DOS has many ntfs read and write driver,but the linux can't for a long time

[Bernd Petrovitsch <bernd@firmix.at>]

On Mon, 2006-01-09 at 17:53 +0100, Oliver Neukum wrote:
> Am Montag, 9. Januar 2006 17:41 schrieb Lee Revell:
> > On Mon, 2006-01-09 at 17:29 +0100, Bernd Petrovitsch wrote:
> > > On Mon, 2006-01-09 at 11:19 -0500, Lee Revell wrote:
> > > > On Mon, 2006-01-09 at 17:14 +0100, Oliver Neukum wrote:
> > > > > Am Montag, 9. Januar 2006 17:04 schrieb Lee Revell:
> > > > > > On Mon, 2006-01-09 at 17:02 +0100, Oliver Neukum wrote:
> > > > > > > Am Montag, 9. Januar 2006 16:15 schrieb Lee Revell:
> > > > > > > > On Mon, 2006-01-09 at 15:28 +0100, Oliver Neukum wrote:
> > > > > > > > > Am Montag, 9. Januar 2006 15:18 schrieb Robert Hancock:
> > > > > > > > > > Yaroslav Rastrigin wrote:
> > > > > > > > > > > Well, I could find more or less reasonable explanation of this behaviour - different VM policies of two OSes and 
> > > > > > > > > > > strangely strong and persistent belief "Free RAM is a wasted RAM" among kernel devs. Free RAM is not a wasted RAM, its a memory waiting to be used ! 
> > > > > > > > > > > Whenever it is needed by apps I'm launching or working with. 
> > > > > > > > > > 
> > > > > > > > > > There is no different VM policy here, Windows behaves quite similarly. 
> > > > > > > > > > It does not leave memory around unused, it uses it for disk cache.
> > > > > > > > > 
> > > > > > > > > That doesn't mean that the rate of eviction is the same.
> > > > > > > > > Is it possible that read-ahead is not aggressive enough?
> > > > > > > > 
> > > > > > > > Enough for what?  What is the exact problem you are trying to solve?
> > > > > > > 
> > > > > > > Quicker application startup.
> > > > > > 
> > > > > > Why do you look to the kernel first?  The obvious explanation is that
> > > > > > Linux desktop apps are more bloated than their Windows counterparts.
> > > > > 
> > > > > It is the most efficient place. An improvement to the kernel will improve
> > > > > all starting times.
> > > > 
> > > > I think you'll get at most a 10% or 20% speedup by improving the kernel,
> > > > while some of these apps (think Nautilus vs Windows Explorer) will need
> > > > to be 1000% faster to seem reasonable to a Windows user.
> > > 
> > > That's easy: Just start nautilus, OOorg, Firefox, a java-vm and
> > > GNOME/KDE infrastructure at login time in the background (*eg* and
> > > mlockall() the more important ones so that the are surely in RAM) and
> > > "starting the app" is only a small program connecting to the respective
> > > process to get a fork() there (e.g. like the "-remote" parameter in the
> > > Mozilla family).
> > 
> > Have you tried this?  I suspect it still takes at least twice as long as
> > on windows.
> > 
> > For example on my system there was already a "nautilus" process but
> > "Places -> Home Folder" still took ~2 seconds to display anything, and
> > ~8 seconds to completely render the window and icons.  On Windows this
> > takes much less than a second.
> 
> Does the Windows Explorer draw icons based only on name and metadata?

Depends on the "View" of that directory and what you mean with
"metadata":
- There are view types that display such mini-icons and/or file details
  and/or contents for images.
- "Metadata" in the Windows-hell means "extension" which you get cheap
  with the filename anyways. There is no thing like "file" or a similar
  attempt to guess the type of contents automagically just for doing
  graphiocal "ls".

	Bernd
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