Proposal for adding O_DIRECT support into JDK 9

[Lu, Yingqi]

Alan,

Thank you for the feedback. We will come up with a more generic API that is flexible for supporting all the platforms that have DirectIO. Will send it here for review soon.

Thanks,
Lucy

>-----Original Message-----
>From: Alan Burlison [mailto:Alan.Burlison at oracle.com]
>Sent: Friday, October 14, 2016 1:28 AM
>To: Lu, Yingqi <yingqi.lu at intel.com>; Brian Burkhalter
><brian.burkhalter at oracle.com>
>Cc: Kharbas, Kishor <kishor.kharbas at intel.com>; nio-dev at openjdk.java.net;
>core-libs-dev at openjdk.java.net; Kaczmarek, Eric <eric.kaczmarek at intel.com>
>Subject: Re: Proposal for adding O_DIRECT support into JDK 9
>
>As has been pointed out already, platforms other than Linux provide similar
>functionality, yet this proposal does not provide any support for them. Even if
>such support isn't added initially, the APIs added for the Linux implementation
>should be generic enough that direct IO support could be added for other
>platforms in the future, and that Java code using direct IO on Linux would work
>on other direct IO enabled platforms as well. My concern is that the proposed
>APIs are too Linux-specific to make that possible.
>
>I'm well aware of the issues in things like Hadoop and Apache Spark, their over-
>reliance on platform-specific functionality and native code has made it extremely
>difficult to get them to work well on platforms other than Linux/x86. We should
>not make the same mistake in Java itself.
>
>--
>Alan Burlison
>--