Re: O_DIRECT question

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Denis Vlasenko wrote:
On Thursday 25 January 2007 21:45, Michael Tokarev wrote:
Phillip Susi wrote:
Denis Vlasenko wrote:
You mean "You can use aio_write" ?
Exactly.  You generally don't use O_DIRECT without aio.  Combining the
two is what gives the big win.
Well, it's not only aio.  Multithreaded I/O also helps alot -- all this,
say, to utilize a raid array with many spindles.

But even single-threaded I/O but in large quantities benefits from O_DIRECT
significantly, and I pointed this out before.

Which shouldn't be true. There is no fundamental reason why
ordinary writes should be slower than O_DIRECT.

Other than the copy to buffer taking CPU and memory resources.

--
Bill Davidsen <[email protected]>
  "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux