Re: why swap at all?

[Wakko Warner]

> > I have a question about that.  I keep a debian mirror on one of my machines. 
> > there is over 70000 files.  If I run find on that tree while it's
> > downloading the file list, it doesn't take as long.  I thought it would be
> > nice if there was some way I could keep that in memory.  The box has 256mb
> > ram no swap.  It is configured as diskless.
> > 
> 
> You mean that if you prime the cache by running find on the tree,
> your actual operation doesn't take as long?

Yup.  Running the mirror doesn't matter really.  I start that before I
retire at the end of the day.

> I don't doubt this. Slab cache is shrunk aggressively compared to
> page cache. Traditionally I think this has been due at least in
> part to some failure cases in the balancing there resulting in slab
> growing out of control with some systems.

Where it gets me is the 2nd mirror I have on a usb disk.  Updating it takes
a while.  Although priming the cache on the machine where the usb disk is is
a bit quicker than where the mirror is (rsync over tcp/ip).  Both disks use
ext3, but the machine the usb is on has way more memory, usb2, and overall
quicker than the other.

> These failure cases should be fixed now, and slab vs pagecache is
> probably something that should be looked at again. I really need
> to get my hands on a 2GB+ system before I'd be game to start
> fiddling with too much stuff though.

I've been wanting to upgrade that machine to 768mb, but I don't know if
it'll handle it.

-- 
 Lab tests show that use of micro$oft causes cancer in lab animals
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