Patch Name: PHKL_13572

Patch Description: s700 10.20 JFS hang,ftruncate on JFS files cumulative patch

Creation Date: 97/12/16

Post Date:  98/01/13

Repost:	98/09/18
	A problem has been discovered with superseding patch
	PHKL_15478, it can freeze one CPU for hours on a MP
	system causing severe system performance degradation.
	Patch PHKL_13572 will be re-released until a replacement
	patch is available.

Hardware Platforms - OS Releases:
	s700: 10.20

Products: N/A

Filesets:
	JournalFS.VXFS-BASE-KRN

Automatic Reboot?: Yes

Status: General Superseded

Critical:
	Yes
	PHKL_13572: HANG
	PHKL_7763: CORRUPTION

Path Name: /hp-ux_patches/s700/10.X/PHKL_13572

Symptoms:
	PHKL_13572:
	System seems to "hang" for 2-10 seconds intermittently
	during heavy filesystem I/O. from dts:
	"The problem seems to be easily reproduced on the
	customer's system using a simple "cp" command to write
	large files into a vxfs filesystem on their EMC Symmetrix
	disks.  During the copy, real-time memory locked
	monitoring processes do not run for several seconds.  The
	side effects first noticed are bad interactive system
	behavior, but the more severe impact is HA products
	triggering warnings or false-failover situations.  Most
	severe are the occasional 10-11 second hangs which result
	in FDDI going off-ring and requiring a re-initialization."

	PHKL_7763:
	Applications using ftruncate(2) on VxFS files could
	possibly loose data.  Corruption has been reported with
	Empress databases, and with Excel 5.0 spreadsheets (via
	LMX sharing a JFS filesystem).

Defect Description:
	PHKL_13572:
	In vx_vnode_flush or vx_inval_list, there is a for-loop
	responsible for travesering the buf chains associated with
	a vnode.  For a large file (>2GB), the buf chain gets
	pretty long and the traversing takes quite a while.
	Since we need to hold the vnode lock while going thought
	the chain, sometime we end up hold the lock for too
	long.  This leads to the symptom descrived above.

	PHKL_7763:
	The VxFS file truncation code was breaking an assumption
	of the buffer cache causing delayed-write buffers to be
	discarded instead of being flushed to disk.  This problem
	would be seen when using version 2 file-systems, but code
	changes in the allocation policies prevent the problem
	from occuring on version 3 file-systems.

SR:
	1653170464 4701377770 5003321760

Patch Files:
	/usr/conf/lib/libvxfs_base.a(vx_bio1.o)

what(1) Output:
	/usr/conf/lib/libvxfs_base.a(vx_bio1.o):
		vx_bio1.c     $Date: 97/12/16 12:16:07 $ $Revision:
			1.7.98.7 $ PATCH_10.20 (PHKL_13572)

cksum(1) Output:
	2524684721 6652 /usr/conf/lib/libvxfs_base.a(vx_bio1.o)

Patch Conflicts: None

Patch Dependencies: None

Hardware Dependencies: None

Other Dependencies: None

Supersedes:
	PHKL_7763

Equivalent Patches:
	PHKL_13573:
	s800: 10.20

	PHKL_13574:
	s700: 11.00
	s800: 11.00

Patch Package Size: 70 KBytes

Installation Instructions:
	Please review all instructions and the Hewlett-Packard
	SupportLine User Guide or your Hewlett-Packard support terms
	and conditions for precautions, scope of license,
	restrictions, and, limitation of liability and warranties,
	before installing this patch.
	------------------------------------------------------------
	1. Back up your system before installing a patch.

	2. Login as root.

	3. Copy the patch to the /tmp directory.

	4. Move to the /tmp directory and unshar the patch:

		cd /tmp
		sh PHKL_13572

	5a. For a standalone system, run swinstall to install the
	    patch:

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_13572.depot

	5b. For a homogeneous NFS Diskless cluster run swcluster on the
	    server to install the patch on the server and the clients:

		swcluster -i -b

	    This will invoke swcluster in the interactive mode and
	    force all clients to be shut down.

	    WARNING: All cluster clients must be shut down prior to the
		     patch installation.  Installing the patch while the
		     clients are booted is unsupported and can lead to
		     serious problems.

	    The swcluster command will invoke an swinstall session in which
	    you must specify:

		alternate root path  -  default is /export/shared_root/OS_700
		source depot path    -  /tmp/PHKL_13572.depot

	    To complete the installation, select the patch by choosing
	    "Actions -> Match What Target Has" and then "Actions -> Install"
	    from the Menubar.

	5c. For a heterogeneous NFS Diskless cluster:

		- run swinstall on the server as in step 5a to install
		  the patch on the cluster server.

		- run swcluster on the server as in step 5b to install
		  the patch on the cluster clients.

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_13572.  If you do not wish to retain a
	copy of the original software, you can create an empty file
	named /var/adm/sw/patch/PATCH_NOSAVE.

	Warning: If this file exists when a patch is installed, the
	         patch cannot be deinstalled.  Please be careful
		 when using this feature.

	It is recommended that you move the PHKL_13572.text file to
	/var/adm/sw/patch for future reference.

	To put this patch on a magnetic tape and install from the
	tape drive, use the command:

		dd if=/tmp/PHKL_13572.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions:
	There is a equivalent patch for 11.00 (PHKL_13574) but
	I can't specify any s700 or s800 or s700/800 platform
	for the 11.00 release.  So I put the comment here.