OpenVMS VMS721_CLIUTL-V0100 Alpha V7.2-1 CLIUTL ECO Summary

TITLE: OpenVMS VMS721_CLIUTL-V0100 Alpha V7.2-1 CLIUTL ECO Summary

Modification Date:  25-JAN-2001
Modification Type:  New Kit
 
NOTE:  An OpenVMS saveset or PCSI installation file is stored
       on the Internet in a self-expanding compressed file.
 
       For OpenVMS savesets, the name of the compressed saveset
       file will be kit_name.a-dcx_vaxexe for OpenVMS VAX or
       kit_name.a-dcx_axpexe for OpenVMS Alpha. Once the OpenVMS
       saveset is copied to your system, expand the compressed
       saveset by typing RUN kitname.dcx_vaxexe or kitname.dcx_alpexe.
 
       For PCSI files, once the PCSI file is copied to your system,
       rename the PCSI file to kitname-dcx_axpexe.pcsi, then it can
       be expanded by typing RUN kitname-dcx_axpexe.pcsi.  The resultant
       file will be the PCSI installation file which can be used to install
       the ECO.
 

 

Copyright (c) Compaq Computer Corporation 2000.  All rights reserved.

OP/SYS:     OpenVMS Alpha

COMPONENT:  CLIUTL

SOURCE:     Compaq Computer Corporation

ECO INFORMATION:

     ECO Kit Name:  VMS721_CLIUTL-V0100
                    DEC-AXPVMS-VMS721_CLIUTL-V0100--4.PCSI
     ECO Kits Superseded by This ECO Kit:  None 
     ECO Kit Approximate Size:  2096 Blocks                    
     Kit Applies To:  OpenVMS Alpha V7.2-1
     System/Cluster Reboot Necessary:  No
     Rolling Re-boot Supported:  No
     Installation Rating:  INSTALL_3
                            3 - To be installed on all systems running
                                the listed versions of OpenVMS which
                                are experiencing the problems described.}
                           
     Kit Dependencies:

       The following remedial kit(s) must be installed BEFORE
       installation of this kit:

         VMS721_UPDATE-V0100
         VMS721_PCSI-V0100

       In order to receive all the corrections listed in this
       kit, the following remedial kits should also be installed:

         VMS721_RMS-V0100


ECO KIT SUMMARY:

An ECO kit exists for CLIUTL on OpenVMS Alpha V7.2-1.  This kit addresses
the following problems:

Problems Addressed In VMS721_CLIUTL-V0100:

   o   Issuing two different SET DEVICE commands can crash  a  system
       at  NSA$SIZE_NSAB.   This is due to invalid argument counts in
       the two $CMKRNL calls.

          Images Affected:   [SYSEXE]SET.EXE


   o   A DCL (Digital command language) $ SHOW CLUSTER  command  will
       hang  on  startup  on cluster-nodes with many SCS ports, e.g.,
       CIPCA,   CIXCD,   MC:...    or   Pxx0:    devices,   if    the
       virtual-circuit  (PB$ path-block) count exceeds four times the
       SCS-node count.  An "SCS-node" is defined as any  SCS-speaking
       node,  such as HSJxx/HSCxx Storage Controllers, RFxx DSSI disk
       controllers, or VMS nodes, etc.

          Images Affected:  [SYSEXE]SHWCLSTR.EXE


   o   SHOW LOGICAL allocates virtual address space based on pagesize
       rather  than  pagelet  size  for Alpha only.  De-allocation of
       used virtual memory was incorrect.

          Images Affected:  [SYSEXE]SHOW.EXE

         
   o   The system STARTUP process will hang in a loop waiting for the
       AUDIT_SERVER  process to start, if the $SET AUDIT/SERVER=START
       command fails.

          Images Affected:  [SYSEXE]SETAUDIT.EXE


   o   Add a new /CONTENTION_POLICY qualifier to SET  RMS_DEFAULT  to
       address locking fairness issues.

       The new Alpha global buffer read-mode lock support  introduced
       in V7.2-1H1 is functionally compatible with both VAX and older
       Alpha releases.  Operations in mixed clusters produce  correct
       results.   However, there is a locking fairness issue that may
       arise with mixed cluster operations.

       In a mixed cluster environment with very high  contention  for
       specific  buckets, it is possible for accesses to write-shared
       files on nodes using  read-mode  bucket  locking  to  dominate
       access  to  a  bucket.   Nodes  without  this support might be
       unable to access the bucket for a protracted period  of  time.
       It  is  also  possible  to  observe comparable behavior on all
       OpenVMS versions when dealing with  accesses  to  write-shared
       files  without  global buffers enabled -- even on a standalone
       system.  A similar fairness issue between lock conversions and
       new  lock  requests  may  be  observed  in  which the new lock
       requests may remain ungranted for an extended period of time.

       This kit provides an interface  for  RMS  support  for  a  new
       option  to  improve  fairness under high contention conditions
       for write-shared files.  The option is  controlled  using  the
       /CONTENTION_POLICY   qualifier   to   the   DCL   command  SET
       RMS_DEFAULT.  The option may be set at  a  process  or  system
       level.   Since  selecting  this option may noticeably increase
       locking  overhead  and  since  many  applications  will  never
       encounter  this issue, the default system behavior leaves this
       option disabled.  A future lock management enhancement  should
       make this fairness workaround unnecessary for later releases.

       The  following  are  valid  PROCESS  keywords   (/SYSTEM   not
       specified) for SET RMS_DEFAULT/CONTENTION_POLICY:

               NEVER          Never use the higher overhead option
                              to improve fairness for any write-shared
                              files accessed by this process; minimal overhead.
                            
               SOMETIMES      Use this option for fairer bucket
                              access (but higher overhead) to any
                              write-shared files with globa"0" CELLSPACING="0" CELLPADDING="0">