On Wed, Sep 30, 1998 at 11:26:13PM -0700, [EMAIL PROTECTED] wrote:
> On 1 Oct, Robert G. Brown wrote:
> > Hmm, never heard of swap not working before. Are you sure you are
> > invoking it correctly? Try the script below. Note that with multiple
> > SCSI disks, swap will be a bit more efficient if the swapfiles are on
> > different disks instead of all in one partition. Using swapfiles
> > instead of swap partitions conserves partitions -- since you need at
> > least four swap spaces to swap a full 512 MB (linux has a 128 MB limit
> > per) you would need to break up a single disk into 5+ partitions,
> > which is a pain.
>
> Is using swap files any faster or slower than using swap partitions?
> -M@
>
Hello,
IIRC using swap _files_ is discouraged on production systems,
as there is always a (very small) risk of deadlock and there is a performance
penalty.
If you need fast swap, use swap partitions on diferent disks,
and specify the same priority.
Ciao
Dietmar
quoting man 2 swapon:
PRIORITY
Each swap area has a priority, either high or low. The
default priority is low. Within the low-priority areas,
newer areas are even lower priority than older areas.
All priorities set with swapflags are high-priority,
higher than default. They may have any non-negative value
chosen by the caller. Higher numbers mean higher prior�
ity.
Swap pages are allocated from areas in priority order,
highest priority first. For areas with different priori�
ties, a higher-priority area is exhausted before using a
lower-priority area. If two or more areas have the same
priority, and it is the highest priority available, pages
are allocated on a round-robin basis between them.
As of Linux 1.3.6, the kernel usually follows these rules,
but there are exceptions.
--
Reporter (to Mahatma Gandhi): Mr Gandhi, what do you think of Western
Civilization? Gandhi: I think it would be a good idea.
Dietmar Goldbeck, E-Mail: [EMAIL PROTECTED]; phone +49-5241-80-7646
