==========================================================================
The checksum's (found through sum -r) of the files that you have received
(other than this README) are as follows:

24174      1 patchSG0000408
48818      4 patchSG0000408.idb
59156   1153 patchSG0000408.onc3_eoe_sw
==========================================================================



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       1.  Patch_SG0000408_Release_Note

       This release note describes patch SG0000408 to IRIX 5.3 with
       XFS.

       1.1  Supported_Hardware_Platforms

       This patch contains bug fixes for all IP5 systems, all IP12
       systems,	all IP17 systems, all IP19 systems, all	IP20
       systems,	and all	IP22 systems.  The software cannot be
       installed on other configurations.


       1.2  Supported_Software_Platforms

       This patch contains bug fixes for ONC3 (version 1021572033)
       on a system running IRIX	5.3 with XFS.  The software cannot
       be installed on other configurations.

       1.3  Bugs_Fixed_by_Patch_SG0000408

       This patch contains fixes for the following bugs	in ONC3
       running on IRIX 5.3 with	XFS.  Bug numbers from Silicon
       Graphics	bug tracking system are	included for reference.

	  o Due	to a deadlock which can	occur when cachefs_fsync is
	    called with	the FSYNC_WAIT flag, cachefs may hang
	    during a sync operation.  (Bug #259761)

	  o CacheFS excessively	allocates kernel memory.  Much of
	    the	memory allocated is not	returned to the	system
	    until all CacheFS file systems have	been unmounted.
	    (Bug #252778)

	    This patch changes CacheFS so that it will return
	    memory to the system by freeing cnode data.	 This may
	    be controlled through two tunable parameters:
	    maxcnodes and cachefs_max_lru.  The	tunable	parameter
	    maxcnodes has been introduced with this patch.  It
	    determines the upper bound for cnode allocation.  This
	    is what might be called a "soft" boundary.	CacheFS	may
	    allocate more than this many cnodes, but once the upper
	    bound has been exceeded, inactive cnodes will be freed.

	    Tuning should be done by setting maxcnodes and
	    cachefs_max_lru to low values (such	as 100 and 10
	    respectively), with	maxcnodes being	greater	than
	    cachefs_max_lru.  These numbers should be increased
	    until the desired combination of performance and memory
	    usage is obtained.	Note that maxcnodes may	be set to
	    be less than or equal to cachefs_max_lru.  Doing so











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	    will cause no problems.  It	will, however, result in
	    all	cnodes not on the lru list being freed (i.e., their
	    storage returned to	the system).

	    Take care to consider file access patterns when tuning.
	    Commands such as du(1) and find(1) will have very
	    different access patterns from make(1), cc(1) and
	    ld(1).

	    The	above tuning method has	been suggested in order
	    that fragmentation of the kernel heap may be avoided.
	    This will minimize both the	total memory allocated to
	    the	kernel and the amount used by CacheFS.	Setting
	    maxcnodes and cachefs_max_lru to higher values and then
	    lowering them is less effective at keeping kernel
	    memory usage low.  This is because the data	allocated
	    by CacheFS will be distributed throughout a	larger heap
	    area.

       1.4  Subsystems_Included_in_Patch_SG0000408

       This patch release includes these subsystems:

	  o patchSG0000408.onc3_eoe_sw.cachefs


       1.5  Installation_Instructions

       Because you want	to install only	the patches for	problems
       you have	encountered, patch software is not installed by
       default.	 After reading the descriptions	of the bugs fixed
       in this patch (see Section 1.3),	determine the patches that
       meet your specific needs.

       If, after reading Sections 1.1 and 1.2 of these release
       notes, you are unsure whether your hardware and software
       meet the	requirements for installing a particular patch,	run
       inst.  The inst program does not	allow you to install
       patches that are	incompatible with your hardware	or
       software.

       Patch software is installed like	any other Silicon Graphics
       software	product.  Follow the instructions in your Software
       Installation Administrator's Guide to bring up the miniroot
       form of the software installation tools.

       Follow these steps to select a patch for	installation:

	 1.  At	the Inst> prompt, type

	     install patchSGxxxxxxx











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	     where xxxxxxx is the patch	number.

	 2.  Initiate the installation sequence. Type

	     Inst> go

	 3.  You may find that two patches have	been marked as
	     incompatible.  (The installation tools reject an
	     installation request if an	incompatibility	is
	     detected.)	 If this occurs, you must deselect one of
	     the patches.

	     Inst> keep	patchSGxxxxxxx

	     where xxxxxxx is the patch	number.

	 4.  After completing the installation process,	exit the
	     inst program by typing

	     Inst> quit



       1.6  Patch_Removal_Instructions

       To remove a patch, use the versions remove command as you
       would for any other software subsystem.	The removal process
       reinstates the original version of software unless you have
       specifically removed the	patch history from your	system.

       versions	remove patchSGxxxxxxx

       where xxxxxxx is	the patch number.

       To keep a patch but increase your disk space, use the
       versions	removehist command to remove the patch history.

       versions	removehist patchSGxxxxxxx

       where xxxxxxx is	the patch number.

       1.7  Known_Problems

















