Re: RFR(s): 8212828: (process) Change the Process launch mechanism default on Linux to be posix_spawn

[Roger Riggs]

Hi Thomas,

The CI tests here ran fine.

Overall looks ok.

Regards, Roger


On 02/06/2019 01:16 PM, Thomas Stüfe wrote:

Hi Roger,

On Wed, Feb 6, 2019 at 4:15 PM Roger Riggs <roger.ri...@oracle.com <mailto:roger.ri...@oracle.com>> wrote:

    Hi Thomas,

    On 02/06/2019 04:29 AM, Thomas Stüfe wrote:

    Hi all

    Bug: https://bugs.openjdk.java.net/browse/JDK-8213192
    webrev:
    
http://cr.openjdk.java.net/~stuefe/webrevs/8213192--(process)-change-the-process-launch-mechanism-default-on-linux-to-be-posix_spawn/webrev.00/webrev/index.html
    
<http://cr.openjdk.java.net/%7Estuefe/webrevs/8213192--%28process%29-change-the-process-launch-mechanism-default-on-linux-to-be-posix_spawn/webrev.00/webrev/index.html>

    (@Roger: I hope you do not mind? The bug is assigned to you but
    since I happened to play around with posix_spawn I prepared this
    webrev. If you rather do this change, that is fine and I will
    leave it to you.)

    no problem, I hadn't gotten to it.  Thanks for proposing it.

    When we added the possibility to use posix_spawn as underlying
    implementation for Runtime.exec() on Linux with
    https://bugs.openjdk.java.net/browse/JDK-8212828, we agreed to
    keep VFORK as default until work on 13 starts. So now would be a
    good time to switch the default to posix_spawn to get a good
    testing window. Note that at SAP we run our VMs internally with
    posix_spawn as default since some months and have not seen problems.

    As for the fix, I added a test which tests that the default is
    indeed posix_spawn - not sure whether this is overdoing it
    though. Also, I use strace for the test, and /bin/true, and while
    strace is usually available and reachable by path resolution, I
    am afraid on some test machines it may not. What do you think,
    should I leave the test out?

    The test is a bit quirky but should work ok.
    I'd leave it in until it fails and re-evaluate then.

    If it fails on some systems, we can either configure them out or
    just skip the test if the process launch of strace fails. (Throw
    SkippedException).

Yes, that makes sense.

    The fix ran through all java/lang/ProcessBuilder jtreg tests ok.

    I'll run the patch through the usual CI build here too.


Thanks. I'll run the test thru the submit repository too.

Cheers, Thomas

    Thanks, Roger

    Thanks, Thomas