Re: [00/17] Large Blocksize Support V3

On Thu, Apr 26 2007, Mel Gorman wrote:
On (26/04/07 20:39), Jens Axboe didst pronounce:
On Thu, Apr 26 2007, Christoph Lameter wrote:
On Thu, 26 Apr 2007, Jens Axboe wrote:

On Thu, Apr 26 2007, Christoph Lameter wrote:
On Thu, 26 Apr 2007, Jens Axboe wrote:

The above can be implemented fairly cleanly, and on a need-to-have
basis. It's not something that'll break drivers.

But its also not going to fix the hacks that we have in the kernel
to deal with > PAGE_SIZE i/o.

No, but that's a _seperate_ issue! Don't keep mixing up the two.

Yes I understand that you want it to be a separate issue so we get get
more rationales for the hacks that we do to avoid the large
order allocations.

Christoph, don't take your frustrations out on me. I've several times in
this thread said that I'd LIKE to have > PAGE_SIZE support in the page
cache. I WROTE the initial pktcdvd driver that is a primary example of
these hacks, I'm very well aware of the pain and bugs involved with
that.

But don't push large pages as the only solution to larger ios, because
that is trivially not true.


Would it be fair to say that your approach and using large pages are not
mutually exclusive solutions? It seems a lot of the debate here is
assuming there is One And Only One Solution for larger ios.

Definitely, there's zero reason they cannot coexist.

--
Jens Axboe

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Relevant Pages

  • Re: [00/17] Large Blocksize Support V3
    ... basis. ... It's not something that'll break drivers. ... But its also not going to fix the hacks that we have in the kernel ...
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  • Re: [00/17] Large Blocksize Support V3
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  • Re: [00/17] Large Blocksize Support V3
    ... It's not something that'll break drivers. ... But its also not going to fix the hacks that we have in the kernel ... Just taking a quick look at pktcdvd that does appear to be a case where ... Now I'm not a block layer expert and my knowledge of the page cache ...
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  • Re: [00/17] Large Blocksize Support V3
    ... On Thu, Apr 26 2007, Christoph Lameter wrote: ... It's not something that'll break drivers. ... But its also not going to fix the hacks that we have in the kernel ...
    (Linux-Kernel)
  • Re: [00/17] Large Blocksize Support V3
    ... It's not something that'll break drivers. ... But its also not going to fix the hacks that we have in the kernel ... Just taking a quick look at pktcdvd that does appear to be a case where ... Now I'm not a block layer expert and my knowledge of the page cache ...
    (Linux-Kernel)