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HP OpenVMS Systems Documentation

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HP OpenVMS DCL Dictionary


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SHOW MEMORY

Displays the availability and usage of those system resources that are related to memory.

Format

SHOW MEMORY


Parameters

None.

Description

The information provided by the SHOW MEMORY command can help you determine whether to change certain system memory resources to improve system performance. The system memory resources are as follows:
Physical memory
Process entry slots and balance slots
Nonpaged and paged dynamic memory
Space in paging and swapping files
File data cache memory usage

When the SHOW MEMORY command is executed, a display is written to SYS$OUTPUT. Depending on which qualifiers you specify, the display shows the following memory resource statistics:

Physical memory usage
Bad page list
Number of pages allocated to an OpenVMS system
Slot usage
Dynamic memory usage (in bytes)
Paging file usage (in blocks)
Dynamic memory
Granularity hint regions for code and data (Alpha/Integrity servers only)
Extended File Cache facility (Alpha/Integrity servers only)
Write bitmap (WBM) memory use (Alpha/Integrity servers only)

For a detailed description of each item displayed, see the examples.


Qualifiers

/ALL (default)

Displays all available information, that is, information displayed by the /FILES, /PHYSICAL_PAGES, /POOL, and /SLOTS qualifiers.

/BITMAP (Alpha/Integrity servers only)

Displays information about memory use by write bitmaps (WBM) used with Host-Based Volume Shadowing (HBVS). If the system parameter SHADOWING is set to 0, no information about bitmaps is displayed because WBM is used only with HBVS.

Note that the memory consumption displayed by SHOW MEMORY is often greater than that displayed by SHOW DEVICE /BITMAP, which displays the exact size (in bytes) of the bitmap. The memory used by a bitmap is allocated in units of pages; if a bitmap uses part of a page of memory, the rest of that page is unavailable for use.

/BUFFER_OBJECTS (Alpha/Integrity servers only)

Displays information about system resources used by buffer objects.

/CACHE[=(keyword[,...])]

Displays information about the Virtual I/O Cache facility or the Extended File Cache facility, depending on which is loaded. The Cache facility information is displayed as part of the SHOW MEMORY and SHOW MEMORY/CACHE/FULL commands.

If the Extended File Cache is loaded, you can specify the following keywords and options:

VOLUME[=device] Requests display of volume-level statistics for the specified volume(s). If no device is specified, defaults to SYS$DISK. Device specifications may be wildcarded; if so, the device specification must be based on the physical device name. Specify VOLUME=* to see statistics for all volumes in cache.
FILE=filespec Requests display of file-level statistics for the specified file(s) in cache. The filespec must contain an explicit or implicit device specification. The filespec may be wildcarded according to RMS rules. Specify FILE=dev:*.* to see statistics for all files in cache for a device. Partially wild file specifications that are satisfied by large numbers of files on disk may incur significant processing overhead during display. By default, both open and closed files are displayed (use the OPEN and CLOSED keywords to further restrict which files are displayed).

Note that this command may fail if you select a large number of files for display. If you receive an error message, reduce the number of selected files and reissue the command.

TOPQIO[= n] Requests display of file-level statistics for the n files in cache with the highest overall QIO count ( n defaults to 10).
TOPHITRATE[= n] Requests display of file-level statistics for the n files in cache with the highest overall cache hit rate ( n defaults to 10).
OPEN Include only open files in the display (default for TOPQIO and TOPHITRATE).
CLOSED Include only closed files in the display.

/EXACT

Use with the /PAGE=SAVE and /SEARCH qualifiers to specify a search string that must match the search string exactly and must be enclosed with quotation marks (" ").

If you specify the /EXACT qualifier without the /SEARCH qualifier, exact search mode is enabled when you set the search string with the Find (E1) key.

/FILES

Displays information about the use of each paging and swapping file currently installed.

/FULL

When used with /POOL, displays additional information about pool area.

When used with /CACHE, displays additional information about the file data cache that is loaded (either VIOC or XFC).

This qualifier is ignored unless the /CACHE or /POOL qualifier is specified explicitly.

/GH_REGIONS

On Alpha, displays information about the granularity hint regions (GHR) that have been established. For each of these regions, information is displayed about the size of the region, the amount of free memory, the amount of memory in use, and the amount of memory released to OpenVMS from the region. The granularity hint regions information is also displayed as part of SHOW MEMORY, SHOW MEMORY/ALL, and SHOW MEMORY/FULL commands.

/HIGHLIGHT[=keyword]

Use with the /PAGE=SAVE and /SEARCH qualifiers to specify the type of highlighting you want when a search string is found. When a string is found, the entire line is highlighted. You can use the following keywords: BOLD, BLINK, REVERSE, and UNDERLINE. BOLD is the default highlighting.

/OUTPUT[=filespec]

/NOOUTPUT

Controls where the output of the command is sent. If you do not enter the qualifier, or if you enter the /OUTPUT qualifier without a file specification, the output is sent to the current process default output stream or device, identified by the logical name SYS$OUTPUT.

If you enter the /OUTPUT qualifier with a partial file specification (for example, specifying only a directory), SHOW is the default file name and .LIS the default file type. If you enter a file specification, it cannot include asterisk (*) and the percent sign (%) wildcard characters.

If you enter the /NOOUTPUT qualifier, output is suppressed.

/PAGE[=keyword]

/NOPAGE (default)

Controls the display of memory information on the screen.

You can use the following keywords with the /PAGE qualifier:

CLEAR_SCREEN Clears the screen before each page is displayed.
SCROLL Displays information one line at a time.
SAVE[= n] Enables screen navigation of information, where n is the number of pages to store.

The /PAGE=SAVE qualifier allows you to navigate through screens of information. The /PAGE=SAVE qualifier stores up to 5 screens of up to 255 columns of information. When you use the /PAGE=SAVE qualifier, you can use the following keys to navigate through the information:

Key Sequence Description
Up arrow key, Ctrl/B Scroll up one line.
Down arrow key Scroll down one line.
Left arrow key Scroll left one column.
Right arrow key Scroll right one column.
Find (E1) Specify a string to find when the information is displayed.
Insert Here (E2) Scroll right one half screen.
Remove (E3) Scroll left one half screen.
Select (E4) Toggle 80/132 column mode.
Prev Screen (E5) Get the previous page of information.
Next Screen (E6), Return, Enter, Space Get the next page of information.
F10, Ctrl/Z Exit. (Some utilities define these differently.)
Help (F15) Display utility help text.
Do (F16) Toggle the display to oldest/newest page.
Ctrl/W Refresh the display.

The /PAGE qualifier is not compatible with the /OUTPUT qualifier.

/PHYSICAL_PAGES

Displays information about the amount of physical memory and the number of free and modified pages.

/POOL

Displays information about the usage of each dynamic memory (pool) area, including the amount of free space and the size of the largest contiguous block in each area.

/RESERVED (Alpha/Integrity servers only)

Displays information about memory reservations.

/SEARCH="string"

Use with the /PAGE=SAVE qualifier to specify a string that you want to find in the information being displayed. Quotation marks are required for the /SEARCH qualifier, if you include spaces in the text string.

You can also dynamically change the search string by pressing the Find key (E1) while the information is being displayed. Quotation marks are not required for a dynamic search.

/SLOTS

Displays information about the availability of partition control block (PCB) vector slots and balance slots.

/UNITS=keyword

Allows you to override the current default specified by SET PROCESS/UNITS so that you can display memory in your choice of blocks or bytes.

Keyword options are:

Option Description
BLOCKS Displays memory in blocks (equivalent to PAGES).
BYTES Displays memory in bytes.
PAGES Displays memory in page format (equivalent to BLOCKS).

/WRAP

/NOWRAP (default)

Use with the /PAGE=SAVE qualifier to limit the number of columns to the width of the screen and to wrap lines that extend beyond the width of the screen to the next line.

The /NOWRAP qualifier extends lines beyond the width of the screen and can be seen when you use the scrolling (left and right) features provided by the /PAGE=SAVE qualifier.


Examples

#1

$ SHOW MEMORY
      
       System Memory Resources on 20-JAN-2001 15:22:04.11 
Physical Memory Usage (pages):   Total      Free     In Use  Modified 
 Main Memory (2.00Gb)           262144    201249      60162       733 
Extended File Cache  (Time of last reset: 18-JAN-2001 17:15:14.33) 
  Allocated (Mbytes)         370.00  Maximum size (Mbytes)    1024.00 
  Free (Mbytes)              317.79  Minimum size (Mbytes)     370.00 
  In use (Mbytes)             52.20  Percentage Read I/Os          72% 
  Read hit rate                  96% Write hit rate                 0% 
  Read I/O count             119363  Write I/O count            46259 
  Read hit count             115283  Write hit count                0 
  Reads bypassing cache          45  Writes bypassing cache         0 
  Files cached open             372  Files cached closed          392  
  Vols in Full XFC mode           0  Vols in VIOC Compatible mode   3 
  Vols in No Caching mode         0  Vols in Perm. No Caching mode  0 
Granularity Hint Regions (pages): Total    Free     In Use   Released  
 Execlet code region               1024       0        586        438 
 Execlet data region                256       0        256          0 
 S0/S1 Executive data region        576       0        576          0 
 Resident image code region        1024       0        830        194 
Slot Usage (slots):               Total    Free   Resident    Swapped 
 Process Entry Slots                647     614         33          0 
 Balance Set Slots                  645     614         31          0 
Dynamic Memory Usage:             Total    Free     In Use    Largest 
 Nonpaged Dynamic Memory (Mb)      4.28    2.38       1.89       2.25 
 Bus Addressable Memory  (Kb)    168.00  128.00      40.00     128.00 
 Paged Dynamic Memory    (Mb)      5.68    3.42       2.26       3.41 
 Lock Manager Dyn Memory (Mb)      1.13    0.00       1.12 
Buffer Object Usage (pages):             In Use       Peak 
 32-bit System Space Windows (S0/S1)          3          3 
 64-bit System Space Windows (S2)             0          0 
 Physical pages locked by buffer objects      3          3 
Memory Reservations (pages):     Group  Reserved    In Use       Type 
 VCC$MIN_CACHE_SIZE                ---     47360     47360  Allocated 
 Total (370.00 Mbytes reserved)            47360     47360 
Swap File Usage (8KB pages):               Index      Free       Size 
 DISK$X6XV_BRAHMA:[SYS0.SYSEXE]SWAPFILE.SYS                                   
                                               1      5168       5168 
Paging File Usage (8KB pages):             Index      Free       Size 
 DISK$X6XV_BRAHMA:[SYS0.SYSEXE]PAGEFILE.SYS                                   
                                             254    215288     215288 
 Total committed paging file usage:                              7418 
Of the physical pages in use, 4951 pages are permanently allocated to 
  OpenVMS.
   
      

This example shows reservable pages. If the reservable pages are a negative value, this indicates that you may want to consider adding to the fixed amount of pagefile space available.

#2

$ SHOW MEMORY/CACHE/FULL
            System Memory Resources on 3-NOV-2001 18:36:12.79
 
Extended File Cache  (Time of last reset: 31-OCT-2001 10:18:07.39)
Allocated (Mbytes)     (1)370.00   Maximum size (Mbytes)   (9)1024.00
Free (Mbytes)          (2)319.75   Minimum size (Mbytes)   (10)  370.0
In use (Mbytes)        (3) 50.25   Percentage Read I/Os    (11)     98%
Read hit rate          (4)    79%  Write hit rate          (12)      0%
Read I/O count         (5) 18110   Write I/O count         (13)    310
Read hit count         (6) 14343   Write hit count         (14)      0
Reads bypassing cache  (7)    37   Writes bypassing cache  (15)      0
Files cached open      (8)   351   Files cached closed     (16)    307   
Vols in Full XFC mode  (17)     0   Vols in VIOC Compatible mode (17) 0 
Vols in No Caching mode(17)     0   Vols in Perm No Caching mode (17) 0
 
I/O Statistics (18) - Distributions (MAX_IO_SIZE: 127 (19))
-------------------------------------------------------
Transfer Size:      Reads    Read Hits     Writes
   1 Block IO:      35053 (20)     34553 (21)      87 (22)
   2 Block IO:        469          284          9
   3 Block IO:      26516        26346         24
   4 Block IO:        348          205          6
   5 Block IO:      13205        13160          0
   6 Block IO:        161          111          0
   7 Block IO:        185          152          0
       .
       .
       .
 114 Block IO:          1            0          0
 116 Block IO:          2            1          0
 121 Block IO:          1            0          0
 
>127<256 Block IO:     12                       0
>255     Block IO:     14                       0
----------------------------------------------------
Totals:             84411        80535        630
 
 
      

Note

This example shows the output for the SHOW MEMORY/CACHE/FULL command on an Alpha system with the Extended File Cache loaded. The SHOW MEMORY/CACHE/FULL command will display different fields on an Alpha system with the Virtual I/O Cache loaded.

Extended File Cache Usage

Shows the use of the Extended File Cache facility on an Alpha system.
(1) Allocated Total amount of system memory in megabytes allocated to the Extended File Cache.
(2) Free Number of allocated megabytes not currently in use by the cache.
(3) In use Number of allocated megabytes that contain valid cached data.
(4) Read hit rate Shows cache read hits as a percentage of read I/Os.
(5) Read I/O count Total number of read I/Os that have been seen by the cache since the last statistics reset.
(6) Read hit count Total number of read I/Os that did not perform a physical I/O, because the data for these was found in the cache since the prior statistics reset.
(7) Reads bypassing cache Total number of reads that bypassed the cache and went directly to disk since the last statistics reset.
(8) Files cached open Total number of open files in cache.
(9) Maximum size (Mbytes) Maximum size of the cache in megabytes.
(10) Minimum size (Mbytes) Minimum size of the cache in megabytes. This displays the value of the memory reservation, VCC$MIN_CACHE_SIZE. See the HP OpenVMS System Manager's Manual for additional information.
(11) Percentage Read I/Os Percentage of read I/Os that occur. For example, a read/write I/O ratio of 100% implies that all were read I/Os.
(12) Write hit rate (Always zero for Extended File Cache, Version 1.)
(13) Write I/O count Total number of write I/Os that have been seen by the cache since the last statistics reset.
(14) Write hit count (Always zero for Extended File Cache, Version 1.)
(15) Writes bypassing cache Total number of writes that bypassed the cache and went directly to disk since the last statistics reset.
(16) Files cached closed Total number of closed files in cache.
(17) Volume modes Total number of volumes in each caching state. Note that the initial release of XFC only supports VIOC compatible mode. Future releases will support full mode.
(18) I/O Statistics Systemwide distribution of I/O sizes (rounded up).
(19) MAX_IO_SIZE Current setting of the system parameter VCC_MAX_IO_SIZE in blocks. The extended file cache (XFC) will only cache files up to this size.
(20) Reads Number of reads for the entire system.
(21) Read Hits Number of reads satisfied from the cache.
(22) Writes Number of writes for the entire system.

#3

$ SHOW MEMORY/CACHE=(VOLUME=*)
 
             System Memory Resources on 20-JAN-2001 15:35:32.51
 
Extended File Cache Volume Statistics:
 
_$7$DKA200: (DISK$X6XV_BRAHMA), Caching mode is VIOC Compatible
Open files        (1)    372      Closed files        (9)    395
Files ever opened (2)   1007      Files ever deposed  (10)    240
Allocated pages   (3)   6405      Locks acquired      (11)    736
Total QIOs        (4) 166552      Read hits           (12) 115984
Virtual reads     (5) 120068      Virtual writes      (13)  46484
Hit rate          (6)     69 %    Read aheads         (14)  11766
Read throughs     (7) 120021      Write throughs      (15)  46484
Read arounds      (8)     47      Write arounds       (16)      0
Ave Disk I/O Resp Time incl cache hits (microseconds)(17)   3497
 
Total of 1 volumes in cache 
 
 
 
 
      

Extended File Cache Usage

Shows the use of the Extended File Cache facility on an Alpha system.
(1) Open files Number of files that are currently open and cached by the extended file cache on this volume at the instant the SHOW command was issued.
(2) Files ever opened Number of times the extended file cache has been requested to open a file on this volume.
(3) Allocated pages Number of main memory data pages currently being used by the extended file cache to contain actual file data, for this volume.
(4) Total QIOs Total number of QIO and PAGE I/O calls received by the extended file cache on this volume.
(5) Virtual reads Cumulative number of Virtual Read requests received by the extended file cache on this volume.
(6) Hit rate Percentage of Total QIOs that were completed by copying data from cache, rather than issuing real I/O to a volume.
(7) Read throughs Number of Virtual Reads that are capable of being satisfied by the extended file cache.
(8) Read arounds Number of Virtual Reads that cannot be satisfied by the extended file cache. Reasons for this include the presence of a non-XFC compliant node in an OpenVMS cluster, and the receipt of an I/O that is larger than VCC_MAX_IO_SIZE.
(9) Closed files Number of closed files the extended file cache has in memory. If a subsequent file access occurs, data will be accessible from main memory rather than having to issue I/O to the real volume.
(10) Files ever deposed Files removed from memory. Reasons the extended file cache may remove a file from its memory include requests for memory from the rest of the system, and conflicting access modes in a cluster.
(11) Locks acquired Current number of file access locks that are in use on this volume.
(12) Read hits Cumulative number of times a read has been satisfied from the data cache.
(13) Virtual writes Cumulative number of virtual write I/Os received on this volume by the cache.
(14) Read aheads Cumulative number of times the extended file cache issued read ahead I/Os on this volume after detecting sequential file I/O virtual reads.
(15) Write throughs Cumulative number of times a virtual write has been capable of modifying cached data.
(16) Write arounds Cumulative number of times a virtual write has been detected that cannot update data in cache memory.
(17) Average Disk I/O Response Time Average disk I/O response time, including cache hits, in microseconds. Note that on a symmetric multiprocessing (SMP) system, the response time only includes that of I/Os starting or finishing on the same CPU. Any physical I/Os are ignored.
#4

$ SHOW MEMORY/CACHE=(VOL=DKA100,TOPQIO=3)
System Memory Resources on 3-NOV-2001 18:36:12.79
 
Extended File Cache Top QIO File Statistics:
 
_$7$DKA200: (DISK$X6Y0_RESD), Caching mode is VIOC Compatible
 
_$7$DKA200:[SYS0.SYSEXE]SYSDUMP.DMP;2 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages   (1)  334      Total QIOs      (6) 1712
Read hits         (2) 1559      Virtual reads   (7) 1712
Virtual writes    (3)    0      Hit rate        (8)   91 %
Read aheads       (4)    0      Read throughs   (9)    0
Write throughs    (5)    0      Read arounds    (10)    0
                               Write arounds   (11)    0
 
_$7$DKA200:[VMS$COMMON.SYSEXE]SYS$QUEUE_MANAGER.QMAN$JOURNAL;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages       931      Total QIOs         1057
Read hits               5      Virtual reads      1044
Virtual writes         13      Hit rate              0 %
Read aheads             2      Read throughs      1044
Write throughs         13      Read arounds          0
                               Write arounds         0
 

_$7$DKA200:[VMS$COMMON.SYSLIB]DECC$SHR.EXE;1 (open) Caching is enabled, active caching mode is Write Through Allocated pages 135 Total QIOs 730 Read hits 673 Virtual reads 730 Virtual writes 0 Hit rate 0 % Read aheads 2 Read throughs 0 Write throughs 0 Read arounds 0 Write arounds 0 Total of 3 files for this volume

Extended File Cache Top QIO File Statistics Usage

Shows the use of the Extended File Cache Top QIO File Statistics facility on an Alpha system.
(1) Allocated pages Number of main memory data pages currently being used by the extended file cache to contain actual file data, for this volume
(2) Read hits Cumulative number of times a read has been satisfied from the data cache.
(3) Virtual writes Cumulative number of virtual write I/Os received on this volume by the cache.
(4) Read aheads Cumulative number of times the extended file cache issued read ahead I/Os on this volume after detecting sequential file I/O virtual reads.
(5) Write throughs Cumulative number of times a virtual write has been capable of modifying cached data.
(6) Total QIOs Total number of QIO and PAGE I/O calls received by the extended file cache on this volume.
(7) Virtual reads Cumulative number of Virtual Read requests received by the extended file cache on this volume.
(8) Hit rate Percentage of Total QIOs that were completed by copying data from cache, rather than issuing real I/O to a volume.
(9) Read throughs Number of Virtual Reads that are capable of being satisfied by the extended file cache.
(10) Read arounds Number of Virtual Reads that cannot be satisfied by the extended file cache. Reasons for this include the presence of a non-XFC compliant node in an OpenVMS cluster, and the receipt of an I/O that is larger than VCC_MAX_IO_SIZE.
(11) Write arounds Cumulative number of times a virtual write has been detected that cannot update data in cache memory.
#5

$ SHOW MEMORY/CACHE=(VOL=DKA100,TOPHITRATE=3)
System Memory Resources on 3-NOV-2001 18:36:12.79
 
Extended File Cache Top Hitrate File Statistics:
 
_$7$DKA200: (DISK$X6Y0_RESD), Caching mode is VIOC Compatible
 
_$7$DKA200:[VMS$COMMON.SYSLIB]SMGSHR.EXE;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages   (1)   16      Total QIOs      (6)  277
Read hits         (2)  267      Virtual reads   (7)  277
Virtual writes    (3)    0      Hit rate        (8)   96 %
Read aheads       (4)    0      Read throughs   (9)  277
Write throughs    (5)    0      Read arounds    (10)    0
                               Write arounds   (11)    0
 
_$7$DKA200:[VMS$COMMON.SYSLIB]UTIL$SHARE.EXE;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages         8      Total QIOs          185
Read hits             178      Virtual reads       185
Virtual writes          0      Hit rate             96 %
Read aheads             1      Read throughs       185
Write throughs          0      Read arounds          0
                               Write arounds         0
 
_$7$DKA200:[VMS$COMMON.SYSLIB]CMA$TIS_SHR.EXE;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages         6      Total QIOs          165
Read hits             159      Virtual reads       165
Virtual writes          0      Hit rate             96 %
Read aheads             2      Read throughs       165
Write throughs          0      Read arounds          0
                               Write arounds         0
 
Total of 3 files for this volume
 
 
      

Extended File Cache Top Hitrate File Statistics Usage

Shows the use of the Extended File Cache Top Hitrate File Statistics facility on an Alpha system.
(1) Allocated pages .Number of main memory data pages currently being used by the extended file cache to contain actual file data, for this volume
(2) Read hits Cumulative number of times a read has been satisfied from the data cache.
(3) Virtual writes Cumulative number of virtual write I/Os received on this volume by the cache.
(4) Read aheads Cumulative number of times the extended file cache issued read ahead I/Os on this volume after detecting sequential file I/O virtual reads.
(5) Write throughs Cumulative number of times a virtual write has been capable of modifying cached data.
(6) Total QIOs Total number of QIO and PAGE I/O calls received by the extended file cache on this volume.
(7) Virtual reads Cumulative number of Virtual Read requests received by the extended file cache on this volume.
(8) Hit rate Percentage of Total QIOs that were completed by copying data from cache, rather than issuing real I/O to a volume.
(9) Read throughs Number of Virtual Reads that are capable of being satisfied by the extended file cache.
(10) Read arounds Number of Virtual Reads that cannot be satisfied by the extended file cache. Reasons for this include the presence of a non-XFC compliant node in an OpenVMS cluster, and the receipt of an I/O that is larger than VCC_MAX_IO_SIZE.
(11) Write arounds Cumulative number of times a virtual write has been detected that cannot update data in cache memory.
#6

$ SHOW MEMORY/CACHE=(FILE=SYS$LOGIN:*.*,OPEN,CLOSED)
System Memory Resources on 3-NOV-2001 18:36:12.79
 
Extended File Cache Statistics:
 
_$7$DKA200:[SYS0.SYSMGR]ACCOUNTNG.DAT;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages   (1)    1      Total QIOs      (6)   17
Read hits         (2)    0      Virtual reads   (7)    1
Virtual writes    (3)   16      Hit rate        (8)    0 %
Read aheads       (4)    0      Read throughs   (9)    0
Write throughs    (5)   16      Read arounds    (10)    0
                               Write arounds   (11)    0
 
_$7$DKA200:[SYS0.SYSMGR]ACME$SERVER.LOG;129 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages         1      Total QIOs            2
Read hits               0      Virtual reads         1
Virtual writes          1      Hit rate              0 %
Read aheads             0      Read throughs         1
Write throughs          1      Read arounds          0
                               Write arounds         0
 
_$7$DKA200:[SYS0.SYSMGR]CLUE$STARTUP_BRAHMA.LOG;935 (closed)
Caching is enabled, active caching mode is Write Through
Allocated pages         2      Total QIOs           32
Read hits               0      Virtual reads         0
Virtual writes         32      Hit rate              0 %
Read aheads             0      Read throughs         0
Write throughs         32      Read arounds          0
                               Write arounds         0
        .
        .
        .
 
_$7$DKA200:[VMS$COMMON.SYSMGR]VMS$AUDIT_SERVER.DAT;1 (open)
Caching is enabled, active caching mode is Write Through
Allocated pages         1      Total QIOs            8
Read hits               3      Virtual reads         8
Virtual writes          0      Hit rate              37 %
Read aheads             1      Read throughs         8
Write throughs          0      Read arounds          0
                               Write arounds         0
  
Total of 50 files for this volume 
 
 
      

Extended File Cache Statistics Usage

Shows the use of the Extended File Cache Statistics facility on an Alpha system.
(1) Allocated pages .Number of main memory data pages currently being used by the extended file cache to contain actual file data, for this volume
(2) Read hits Cumulative number of times a read has been satisfied from the data cache.
(3) Virtual writes Cumulative number of virtual write I/Os received on this volume by the cache.
(4) Read aheads Cumulative number of times the extended file cache issued read ahead I/Os on this volume after detecting sequential file I/O virtual reads.
(5) Write throughs Cumulative number of times a virtual write has been capable of modifying cached data.
(6) Total QIOs Total number of QIO and PAGE I/O calls received by the extended file cache on this volume.
(7) Virtual reads Cumulative number of Virtual Read requests received by the extended file cache on this volume.
(8) Hit rate Percentage of Total QIOs that were completed by copying data from cache, rather than issuing real I/O to a volume.
(9) Read throughs Number of Virtual Reads that are capable of being satisfied by the extended file cache.
(10) Read arounds Number of Virtual Reads that cannot be satisfied by the extended file cache. Reasons for this include the presence of a non-XFC compliant node in an OpenVMS cluster, and the receipt of an I/O that is larger than VCC_MAX_IO_SIZE.
(11) Write arounds Cumulative number of times a virtual write has been detected that cannot update data in cache memory.
#7

$ SHOW MEMORY/PHYSICAL_PAGES
              System Memory Resources on  3-NOV-2001 16:11:30.76
Physical Memory Usage (pages): Total (1)  Free (2)   In Use (3)  Modified (4)
Main Memory (32.00Mb)          65536   44233      20955         308
 
Of the physical pages in use, 10970 pages are permanently allocated
to VMS.
 
 
      

Physical Memory Usage

Shows the use of physical memory.
(1) Total Number of physical memory pages available for general system use. Multiport memory pages used for shared memory global sections, mailboxes, and common event blocks are not included in this number.
(2) Free Number of pages on the free page list.
(3) In Use Number of pages currently being used. This number is calculated by adding the number of pages on the free, modified, and bad lists and then subtracting that sum from the total number of available pages.
(4) Modified Number of pages on the modified page list.

Bad Page List

Shows the contents of the bad page list.

Note

This display is written only when there are pages on the bad page list.
Total Number of pages on the bad page list.
Dynamic Number of memory errors detected after the system was booted.
I/O Errors Number of errors detected during page fault handling.
Static Number of memory errors detected during boot-time scan.

By default, either single-bit or double-bit errors cause the pages to be removed during the boot-time scan.

Pages Allocated to OpenVMS

Any SHOW MEMORY display that includes the physical memory display concludes with the number of pages permanently allocated to the OpenVMS system. These pages include nonpaged executive code and data, the PFN database, nonpaged dynamic memory, the interrupt stack, and the system page table.
#8

$ SHOW MEMORY/SLOTS
              System Memory Resources on 3-NOV-2001 16:11:35.31
Slot Usage (slots):       Total (1)   Free (2)  Resident (3)  Swapped (4)
Process Entry Slots          75       28          46          1
Balance Set Slots            70       26          44          0
 
 
      

Slot Usage (slots)

Displays the use of process entry slots and balance set slots.
(1) Total Number of process entry slots (the value of the system parameter MAXPROCESSCNT) and balance set slots (the value of the system parameter BALSETCNT) permanently allocated when the system was bootstrapped.
(2) Free Number of slots currently available.
(3) Resident Number of slots currently used by memory-resident processes. The number of balance set slots in use can never be any larger than the number of process entry slots in use because the SWAPPER and NULL processes have process entry slots but do not require balance set slots.
(4) Swapped Number of slots used by outswapped processes. For process entry slots, this number includes all processes that have been partially outswapped. For balance set slots, this number includes those processes that have had their process bodies outswapped but have process headers that are still resident.
#9

$ SHOW MEMORY/POOL
 
              System Memory Resources on  5-DEC-2001 03:59:35.29
 
Dynamic Memory Usage (bytes):   Total (1)    Free (2) In Use (3) Largest (4)
  Nonpaged Dynamic Memory    24993792   23511872   1481920   23363776
  Bus Addressable Memory       131072     114688     16384     114688
  Paged Dynamic Memory        5799936    3530784   2269152    3530176
  Lock Manager Dynamic Memory 1048576     254976    793600
 
 
      

Dynamic Memory Usage (in bytes)

Shows the use of the nonpaged and paged pool areas that allocate variably sized blocks.
(1) Total Total number of bytes set aside for each area.
(2) Free Total amount of free space in each dynamic memory area.
(3) In Use Amount of space currently allocated from each area. This number is the total size minus the number of free bytes.
(4) Largest Size of the largest contiguous block in each area. For the paged pool, this number represents the largest block that can be allocated. For the nonpaged pool, an allocation request larger than this number will cause the nonpaged pool to grow (if other constraints allow growth). This attribute does not apply to the lock manager, as all items for the lock manager are the same size.
#10

$ SHOW MEMORY/POOL/FULL
              System Memory Resources on  5-DEC-2001 03:59:35.29
 
Nonpaged Dynamic Memory                   (Lists + Variable) 
 Current Size (bytes)    (1) 24993792 Current Size (pagelets)  (1)  48816
 Initial Size (NPAGEDYN) (2) 24993792 Initial Size (pagelets)  (2)  48816
 Maximum Size (NPAGEVIR) (3)499998720 Maximum Size (pagelets)  (3) 976560
 Free Space (bytes)      (4) 22230144 Space in Use (bytes)     (5)2763648
 Largest Variable Block  (6) 19676672 Smallest Variable Block  (7)   2176
 Number of Free Blocks   (8)    38334 Free Blocks LEQU 64 Bytes(9)      0
 Free Blocks on Lookasides(16)  38330 Lookaside Space (bytes)     2537472
 
Bus Addressable Memory                    (Lists + Variable) 
 Current Size (bytes)    (1)   131072 Current Size (pagelets)  (1)    256
 Initial Size (NPAGEDYN) (2)   131072 Initial Size (pagelets)  (2)    256
 Free Space (bytes)      (4)   114688 Space in Use (bytes)     (5)  16384
 Largest Variable Block  (6)   114688 Smallest Variable Block  (7) 114688
 Number of Free Blocks   (8)        1 Free Blocks LEQU 64 Bytes(9)      0
 Free Blocks on Lookasides(16)      0  Lookaside Space (bytes)          0
 
Paged Dynamic Memory                      (Lists + Variable)         
 Current Size (MB)       (1)    22.88 Current Size (pagelets)   (1) 46864
 Free Space (MB)         (4)    21.96 Space in Use (MB)         (5)  0.91
 Largest Variable Block  (6)    21.77 Smallest Variable Block(MB)(7)21.77
 Number of Free Blocks   (8)      166 Free Blocks LEQU 64 Bytes  (9)    4
 Free Blocks on Lookasides(16)     165 Lookaside Space (KB)        201.85
 Over-limit Lookaside Blocks(17)     3 Over-limit Space (KB)         7.45
 
Lock Manager Dynamic Memory                                
 Current Size (Mbytes)   (1)    13.85 Current Size (pages)    (1)    1774
 Free Space (Mbytes)     (4)    10.06 Hits                    (12)   54050
 Space In Use            (5)     3.79 Misses                  (13)    1664
 Number of Empty Pages   (10)      26 Expansions               (14)    1792
 Number of Free Packets  (11)   41244 Packet Size              (15)     256
 
 
      

Dynamic Memory

Shows the use of dynamic memory areas consisting of variably sized blocks.
(1) Current Size Current size (in 512-byte pagelets on Alpha ) of each dynamic memory area. For the lock manager display, the unit of measurement is megabytes.
(2) Initial Size Initial size of nonpaged dynamic memory and the name of the system parameter (NPAGEDYN) that controls this size.
(3) Maximum Size Maximum size to which nonpaged dynamic memory can grow and the name of the system parameter (NPAGEVIR) that controls this size.
(4) Free Space Amount of free space in each dynamic memory area.
(5) Space in Use Amount of space currently allocated from each area.
(6) Largest Block Size of the largest contiguous area in each pool area.
(7) Smallest Block Size of the smallest hole (free block) in each pool area.
(8) Free Blocks Total number of free blocks in each pool area. The size of this number is a measure of pool fragmentation.
(9) Blocks LEQU 64 Number of free blocks that are 64 bytes long or shorter. This number is another measure of pool fragmentation because while allocation of these small blocks is unlikely, they contribute to the allocation time whenever an allocation request is made.
(10) Empty Pages Number of pages that do not have any packets allocated.
(11) Free Packets Total number of packets not in use. This number is the sum of free packets from partially used pages and the packets of all Empty Pages.
(12) Hits Total number of packet allocations.
(13) Misses Total number of packet allocation requests that could not be satisfied because the number of packets requested were not available. A miss causes dynamic memory to expand by one page to satisfy the packet allocation request.
(14) Expansions Total number of times that dynamic memory increased by a page to satisfy packet allocation requests.
(15) Packet Size Packet size of 256 bytes, which is used by the lock manager to hold either a lock block data structure or a resource block data structure.
(16) Lookasides Free Blocks Total number of memory packets placed on "lookaside lists". If a packet of the correct size is on a lookaside list, it can be allocated very quickly and efficiently, however, it cannot then be used as part of any other size packet. An excess of packets on the lookaside list can be a cause for the inability to allocate other sizes.
(17) Over-limit Lookaside Blocks Total number of memory packets that exist on "lookaside lists" that are no longer actively used because the SYSGEN parameter PAGED_LAL_SIZE was lowered. These packets will be available for use again if the SYSGEN parameter is increased to include them, or if there was a paged pool shortage and they are reclaimed. If there are no lookaside list packets on these "over-limit" lists then this line will not appear.
#11

$ SHOW MEMORY/FILES
        System Memory Resources on 22-MAY-2001 19:04:19.67
Swap File Usage (8KB pages):              Index (1)     Free     Size
DISK$ALPHASYS:[SYS48.SYSEXE]SWAPFILE.SYS      1         904      904
DISK$SWAP:[SYS48.SYSEXE]SWAPFILE.SYS;1        2        1048     1048
 
  Total size of all swap files:                                 1952
 
Paging File Usage (8KB pages):            Index (2)     Free     Size
DISK$PAGE:[SYS48.SYSEXE]PAGEFILE.SYS;1      253       16888    16888
DISK$ALPHASYS:[SYS48.SYSEXE]PAGEFILE.SYS    254       16888    16888
 
  Total size of all paging files:                              33776
  Total committed paging file usage:  (3)                        1964
 
      

Paging File Usage (in blocks)

Shows the usage of paging and swapping files.
(1) Swap File Usage Number of swap files. Begins with an index value of 1 and increases in count.
(2) Paging File Usage Number of page files. Begins with an index value of 254 and decreases in count.
(3) Total Paging File Usage Total committed page file usage. As in previous releases, more pages can reside in page-file sections systemwide than would fit into installed page files.


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