Re: batched write

Hans Reiser
2006-06-19T09:05:25Z

Nix wrote:

>On 17 Jun 2006, Hans Reiser prattled cheerily:
>
>
>>If the FS is called per page, then it turns out that 3) costs more than
>>1) and 2) for sophisticated filesystems. As we develop fancier and
>>fancier plugins this will just get more and more true. It decreases CPU
>>usage by 2x to use per sys_write calls into reiser4 rather than per page
>>calls into reiser4.
>>
>>
>
>This seems to me to be something that FUSE filesystems might well like,
>too: I know one I'm working on would like to know the real size of the
>original write request (so that it can optimize layout appropriately
>for things frequently written in large chunks; the assumption being that
>if it's written in large chunks it's likely to be read in large chunks
>too).
>
>
>
Hi Nix,

Forgive myn utter ignorance of fuse, but does it currently context
switch to user space for every 4k written through VFS?