Re: Linux should better cope with power failure

Otto Wyss
2001-03-19T22:37:08Z

Jeremy Jackson wrote:
>
> Brian Gerst wrote:
>
> > "Richard B. Johnson" wrote:
> > >
> > > On Mon, 19 Mar 2001, Otto Wyss wrote:
> > >
> > > > Lately I had an USB failure, leaving me without any access to my system
[..]
> > > Unix and other such variants have what's called a Virtual File System
> > > (VFS). The idea behind this is to keep as much recently-used file stuff
> > > in memory so that the system can be as fast as if you used a RAM disk
> > > instead of real physical (slow) hard disks. If you can't cope with this,
> > > use DOS.
> >
> > At the very least the disk should be consistent with memory. If the
> > dirty pages aren't written back to the disk (but not necessarily removed
> > from memory) after a reasonable idle period, then there is room for
> > improvement.
>
> They are. If you leave your machine one for a minute or so (probably less is ok,
> but I don't know) the kernel will flush dirty buffers... fsck will complain, but the
> file's

There was at least 15min I waited without doing anything (how could I
without any imput device). I was editing a file with vim and the usual
bunch of demons where running mostly doing nothing. I don't know if all
the complains from fsck where due to open files or dirty cache pages. I
wouldn't complain if there was any heavy activity but there was allmost none.

> *data* blocks will be on the disk. There are way more reasons that this is a silly
> and annoying thread. You should read more about things like
> asynchronous/synchronous filesystems,
> lazy-write cacheing, etc, etc,. If you know how to write software and/or configure
> your system,
> you can avoid all of these problems. Or use a journaling filesystem ext3/xfs, etc.
> But I tire of this...

So in real live you would propose to put fences and nets everywhere to
prevent children from possibly falling in abyses?

O. Wyss