Hi Joe,

I do not know of any specific skew issues at the resolutions used. For example, Linux records the start time in ticks (1/60th to 100th of a second), not the full resolution of the time of day clock. Typically, the child start time is at least a bit later than the parent. If the maximum possible skew was known or estimated, the comparison could take that into account. For example, I would expect the skew across processors to be less than 1sec (or more likely 10ms) or there would be bigger issues among native processes.

Thanks, Roger


On 12/1/15 8:54 PM, Joseph D. Darcy wrote:
Hi Roger,

Looks fine.

Do you know if there are clock skew issues to be concerned with if the parent and child are spawned on different CPUs?

Thanks,

-Joe

On 12/1/2015 5:49 PM, Roger Riggs wrote:
Please review this change in ProcessHandle to validate parent pids provided by the OS. Children of a process have start times that are the same or later than the parent.
The implementation of descendants(), and children(), and getParent()
are updated to validate the parent pid.

The problem is most pronounced on Windows; the parent pid reported for a
process may be stale if the parent exited.  The validation is applied in
platform neutral code and used on all platforms.  Platform specific code
is used on Windows for getParent(); the Linux platforms do the right thing.

Webrev:
http://cr.openjdk.java.net/~rriggs/webrev-validate-ppid-8143879/

Issue:
   https://bugs.openjdk.java.net/browse/JDK-8143876

Thanks, Roger



Reply via email to