OpenVMS AXPSYS13_061 Alpha V6.1 VIOC__Locking ECO Summary

 
NOTE:  An OpenVMS saveset or PCSI installation file is stored
       on the Internet in a self-expanding compressed file.
       The name of the compressed file will be kit_name-dcx_vaxexe
       for OpenVMS VAX or kit_name-dcx_axpexe for OpenVMS Alpha.
 
       Once the file is copied to your system, it can be expanded
       by typing RUN compressed_file.  The resultant file will
       be the OpenVMS saveset or PCSI installation file which
       can be used to install the ECO.
 
Copyright (c) Digital Equipment Corporation 1995.  All rights reserved.

PRODUCT:    OpenVMS Alpha

COMPONENTS: Virtual I/O Cache (VIOC) 
            Locking 

            LOCKING.EXE
            SYS$VCC.EXE
            SYS$VCC_MON.EXE
            SYS$CLUSTER.EXE

SOURCE:     Digital Equipment Corporation

ECO INFORMATION:

     ECO Kit Name:  AXPSYS13_061
     ECO Kits Superseded by This ECO:  AXPSYS05_061
     ECO Kit Approximate Size:  1200 Blocks
     Kit Applies To:  OpenVMS Alpha V6.1, V6.1-1H1, V6.1-1H2

     NOTE:  This ECO should be applied to all OpenVMS Alpha
            V6.1, V6.1-1H1, and V6.1-1H2 systems.

     System Reboot Necessary:  Yes


      **************************** NOTE **********************************
 
       If ALPSHAD09_061 or greater is already installed on your system,
       there is no need to install this ECO kit.

      ********************************************************************


ECO KIT SUMMARY:

An ECO kit exists for Virtual I/O Cache and Locking on OpenVMS Alpha
V6.1 through V6.1-1H2.  This kit addresses the following problems: 

Problems addressed in the AXPSYS13_061 Kit:

  o  A race condition may occur when a CFCB (Cache File Control
     Block) is being deleted by the XQP and cache space is
     being reclaimed from a LIMBO file.

     This problem is fixed in OpenVMS Alpha V6.2

  o  Under certain conditions, a fork lock used by the virtual
     I/O cache may be created with an incorrect length.  This
     results in unsynchronized data access which can cause
     corruption.

Problems addressed in the AXPSYS05_061 Kit:

  o  If a multi-programming application uses a non-homogenous 
     access pattern to a file which is resident in Virtual I/O 
     cache, there is a possibility that the size returned in the 
     I/O status block from a READ operation will be truncated.

     This problem is fixed in OpenVMS Alpha V6.2

  o  If a clustered application uses a large number of concurrent
     processes to perform file operations consisting of an OPEN, WRITE,
     and CLOSE sequence repetitively on the same data file, data
     corruption may occur. 

     This problem is fixed in OpenVMS Alpha V6.2

  o  In a multi-programming environment where a significant 
     amount of NEW data from a file is being loaded into the 
     cache concurrently by multiple processes, the system may
     HANG.

     This problem is fixed in OpenVMS Alpha V6.2

  o  In a VMS cluster, if VCC_MAXSIZE is set to a value which is too
     low, the following console message may be seen during the boot of
     one of the cluster members: 

        Insufficient system page table space for VIOC cache

     This will permit the Virtual I/O Cache function to run on other
     members of the cluster even though it is not running on this
     member.  This may lead to data corruption.

     This problem is fixed in OpenVMS Alpha V6.2


INSTALLATION NOTES:

In order for the corrections in this kit to take effect, the system
must be rebooted.  If the system is a member of a VMScluster, the 
entire cluster should be rebooted. 

axpsys13_061.README
axpsys13_061.CHKSUM
axpsys13_061.CVRLET_TXT
axpsys13_061.a-dcx_axpexe