Re: [PATCH] updated reiser4 - reduced cpu usage for writes by writing more than 4k at a time (has implications for generic write code and eventually for the IO layer)

Hans Reiser
2006-05-24T17:55:48Z

Tom Vier wrote:

>On Tue, May 23, 2006 at 01:14:54PM -0700, Hans Reiser wrote:
>
>
>>underlying FS can be improved. Performance results show that the new
>>code consumes 40% less CPU when doing "dd bs=1MB ....." (your hardware,
>>and whether the data is in cache, may vary this result). Note that this
>>has only a small effect on elapsed time for most hardware.
>>
>>
>
>Write requests in linux are restricted to one page?
>
>
>
It may go to the kernel as a 64MB write, but VFS sends it to the FS as
64MB/4k separate 4k writes.