Bernd Eckenfels wrote:You don't need to zero out swapfiles. You can fill them with anything,
In article <20050710014559.GA15844@xxxxxxxxxxxx> you wrote:
You misunderstood entirely what I said.There is no portable/documented way to grow a file without having the file
system null its content. However why is that a problem, you dont create
those files very often. Besides it is better for the OS to be able to asume
that a page with zeros in it is equal to the page on fresh swap.
Linux doesn't grow swapfiles at all. It uses what's there at mkswap time.
So are you saying that if I create a swap partition it's best to use dd to
zero it out before mkswap? If no, then why would a file be different? I
know there's no documented way to create a file of given size without
writing content. I saw windows grow a pagefile several meg in less than a
second so I'm sure that it doesn't zero out the space first.
As far as portable, we're talking about linux, portability is not an issueYou can create 50M quickly - even if it actually have to be written. If
in this case. I myself don't use swap files (or partitions), however, there
was a project I recall that would dynamically add/remove swap as needed. Creating a file of 20-50mb quickly would have been beneficial.