Re: Is there a "make hole" (truncate in middle) syscall?

Rob Landley
2003-12-05T00:02:33Z

On Thursday 04 December 2003 15:10, Szakacsits Szabolcs wrote:
> On Thu, 4 Dec 2003, Rob Landley wrote:
> > What are the downsides of holes? [...] is there a performance penalty to
> > having a file with 1000 4k holes in it, etc...)
>
> Depends what you do, what fs you use. Using XFS XFS_IOC_GETBMAPX you might
> get a huge improvement, see e.g. some numbers,
>
> http://marc.theaimsgroup.com/?l=reiserfs&m=105827549109079&w=2
>
> The problem is, 0 general purpose (like cp, tar, cat, etc) util supports
> it, you have to code your app accordingly.

Okay, I'll bite. How would one go about adding hole support to cat? :)

Adding hole support to busybox's cp and tar is on my to-do list. (Pretty far
down on the list, but still...)

> Szaka

Rob