[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re[4]: Jewish List (was: Re: The new kid on the block.)
"Peter L. Peres" <plp@actcom.co.il> wrote:
> On Mon, 4 Jan 1999, Evgeny Stambulchik wrote:
> > On the other hand, in the case of improper shutdown (power down, for
> > example), having a large active file raises the probability of fs errors
> > on that partition and thus, chances of fsck to fail in the auto repair
> > mode on the following boot.
>
> FYI the swap file is NOT open as far as the system knows (the cache does
> not operate on swap blocks).
Sure.
> Also it is not e2fsck inside
I don't quite understand what you meant by that. ext2 (or any other fs, for that
matter) doesn't care what's inside a file.
> so I think that
> it is not checked in the way you think. Its size/block count never
> changes.
Of course. Power faults cause the OS to leave a fs not sync'ed. But, *as well*,
the disk write operations during a power fault may lead to a *physical*
misplacement of the disk heads, so a data being written may happen to be
(partially) written to a block which is not part of the swap file. An extreme
case of such a mechanical misbehaviour is destroying the magnetic layer of the
disk at some place. Now, if the swap is physically separated from the normal
file systems, the bad chances are proportional to the (swap partition boundary
length)/(swap partition area) ratio. The rule is the same for a swap file, but
since the file is not garanteed to occupy a contigious chunk of the disk
surface, the above ratio for a file is generally higher. BTW, this (the
fragmentation) is one of the reasons why swap files are slower than swap
partitions.
Regards,
Evgeny
--
____________________________________________________________
/ Evgeny Stambulchik <fnevgeny@plasma-gate.weizmann.ac.il> \
/ Plasma Laboratory, Weizmann Institute of Science, Israel \ \
| Phone : (972)8-934-3610 == | == FAX : (972)8-934-3491 | |
| URL : http://plasma-gate.weizmann.ac.il/~fnevgeny/ | |
| Finger for PGP key >=====================================+ |
|______________________________________________________________|