Bug ID: JDK-6850720 (process) Use clone(CLONE_VM), not fork, on Linux to avoid swap exhaustion

JDK-6850720 : (process) Use clone(CLONE_VM), not fork, on Linux to avoid swap exhaustion

Type: Bug
Component: core-libs
Sub-Component: java.lang
Affected Version: 6

Priority: P4
Status: Resolved
Resolution: Fixed
OS: linux
CPU: unknown

Submitted: 2009-06-12
Updated: 2010-04-03
Resolved: 2009-06-22

Versions (Unresolved/Resolved/Fixed)

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Unresolved : Release in which this issue/RFE will be addressed.
Resolved: Release in which this issue/RFE has been resolved.
Fixed : Release in which this issue/RFE has been fixed. The release containing this fix may be available for download as an Early Access Release or a General Availability Release.

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JDK 7
7 b62Fixed

Related Reports

Relates :	JDK-7021006 - (process) Remove disabled clone-exec feature
Relates :	JDK-7034935 - Partial backport of Process.exec fixes from JDK7 to JDK6
Relates :	JDK-5049299 - (process) Use posix_spawn, not fork, on S10 to avoid swap exhaustion
Relates :	JDK-6853336 - (process) disable or remove clone-exec feature (6850720)

Description

On Linux it is possible to use clone with CLONE_VM, but not CLONE_THREAD,
which is like fork() but much cheaper and avoids swap exhaustion due to momentary
overcommit of swap space.  One has to be very careful in this case to not mutate global
variables such as environ, but it's worth it.

Comments

EVALUATION This fix did not work out on 32-bit Linux, and was reversed in b62 using bug-ID 6853336. For more information and history on this issue, see: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6853336 http://mail.openjdk.java.net/pipermail/core-libs-dev/2009-June/001853.html http://sources.redhat.com/bugzilla/show_bug.cgi?id=10311

23-06-2009

EVALUATION this is the implementation of 5049299 for linux

12-06-2009