From owner-freebsd-hackers Wed Nov 14 12:46:20 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from zcars0m9.nortelnetworks.com (zcars0m9.nortelnetworks.com [47.129.242.157]) by hub.freebsd.org (Postfix) with ESMTP id 9AA1F37B405 for ; Wed, 14 Nov 2001 12:46:09 -0800 (PST) Received: from zcars04e.ca.nortel.com (zcars04e.ca.nortel.com [47.129.242.56]) by zcars0m9.nortelnetworks.com (8.11.0/8.11.0) with ESMTP id fAEKjNS08591 for ; Wed, 14 Nov 2001 15:45:23 -0500 (EST) Received: from zcard00m.ca.nortel.com by zcars04e.ca.nortel.com; Wed, 14 Nov 2001 15:45:57 -0500 Received: from zcard0ka.ca.nortel.com ([47.129.242.162]) by zcard00m.ca.nortel.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2653.13) id WNFSCLRJ; Wed, 14 Nov 2001 15:45:06 -0500 Received: from hcarp00g (hcarp00g.ca.nortel.com [47.196.31.114]) by zcard0ka.ca.nortel.com with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2653.13) id PX30TGT0; Wed, 14 Nov 2001 15:45:05 -0500 Date: Wed, 14 Nov 2001 15:47:32 -0500 (EST) X-Sybari-Space: 00000000 00000000 00000000 From: "Andrew Atrens" X-X-Sender: atrens@hcarp00g.ca.nortel.com To: hackers@freebsd.org Subject: linux JVMs not handling SEGV well. Message-ID: <20011114152822.G3841-100000@hcarp00g.ca.nortel.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Orig: Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG All, I'm using 4.x-stable, linux-base-6.x, and am encountering a lot of turbulence with both Sun's jdk1.3.x HotSpot JVM and IBM's linux jdk1.3.x JVM. I have a buggy 3rdparty java app that occasionally causes a null pointer exception to be thrown. While not fatal for the app (the exception is correctly caught), it's most often fatal for the JVM. The SUN jvm SEGV's ( doesn't correctly catch the SIGNAL ), while the IBM jvm seems to get locked in kernel mode - only responding to SIGKILL and chewing up tons of 'system' cpu time. The common denominator here is that both JITs utilize linux threads. When I use a non-threaded JIT, the problem doesn't occur. The problem is readily reproducible, but I'm not sure how to debug it. I've played with truss and ktrace, but I think it's time to begin thinking about using the kernel debugger. Anyone have suggestions on the best way to proceed ? Andrew. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message