>>>>> "re" == Richard Elling <[EMAIL PROTECTED]> writes:
re> Mike, many people use this all day long and seem to be quite
re> happy. I think the slow death spiral might be overrated :-)
I don't think it's overrated at all. People all around me are using
this dynamic_pager right now, and they just reboot when they see too
many pinwheels. If they are ``quite happy,'' it's not with their
pager.
The pinwheel is part of a Mac user's daily vocabulary, and although
they generally don't know this, it almost always appears because of
programs that leak memory, grow, and eventually cause thrashing. They
do not even realize that restarting Mail or Firefox will fix the
pinwheels. They just reboot.
so obviously it's an unworkable approach. To them, being forced to
reboot, even if it takes twenty minutes to shut down as long as it's a
clean reboot, makes them feel more confident than Firefox unexpectedly
crashing. For us, exactly the opposite is true.
I think dynamic_pager gets it backwards. ``demand'' is a reason *NOT*
to increase swap. If all the allocated pages in swap are
cold---colder than the disk's io capacity---then there is no
``demand'' and maybe it's ok to add some free pages which might absorb
some warmer data. If there are already warm pages in swap
(``demand''), then do not satisfy more of it, instead let swap fill
and return ENOMEM.
They see demand as capacity rather than temperature but...the machine
does need to run out of memory eventually. Don't drink the
dynamic_pager futuristic kool-aid. It's broken, both in theory and in
the day-to-day experience of the Mac users around me.
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