topic Re: Memory permanently allocated to OpenVMS in Operating System - OpenVMS

Memory permanently allocated to OpenVMS

Kevin Carter_3 — Mon, 09 Aug 2010 15:37:16 GMT

We have 2 AlphaServer DS20E's both running OpenVMS 8.3. Doing a show memory command on one server shows 1.49 GB of memory permanently allocated to OpenVMS; while the same command on the other shows 2.22 GB permanently allocated to OpenVMS. With only 4 GB of memory this seems a little excessive; so wondering why the difference?

Thanks in advance
KC

Re: Memory permanently allocated to OpenVMS

Ian Miller. — Mon, 09 Aug 2010 15:49:44 GMT

See
$ MCR SYSMAN RESERVED_MEMORY LIST

Re: Memory permanently allocated to OpenVMS

Kevin Carter_3 — Mon, 09 Aug 2010 15:56:35 GMT

SYSMAN> RESERVED_MEMORY LIST
%SYSMAN-I-NODERR, error returned from node
-RMS-E-FNF, file not found

Re: Memory permanently allocated to OpenVMS

Steven Schweda — Mon, 09 Aug 2010 19:09:30 GMT

> SYSMAN> RESERVED_MEMORY LIST
> %SYSMAN-I-NODERR, error returned from node
> -RMS-E-FNF, file not found

Same here (Alpha, V8.3):

SYSMAN> RESERVED_MEMORY LIST
%SYSMAN-I-NODERR, error returned from node ALP
-RMS-E-FNF, file not found

Also apparently not very informative (or, at
least, not very interesting):

SYSMAN> RESERVED_MEMORY SHOW
SYSMAN>

Of course, around here, the "permanently
allocated" memory is less of a worry:

alp $ show memo
[...]
Physical Memory Usage (pages): Total Free In Use Modified
Main Memory (2.00GB) 262144 75152 182317 4675
[...]
Memory Reservations (pages): Group Reserved In Use Type
Total (0 bytes reserved) 0 0
[...]
Of the physical pages in use, 10872 pages are permanently allocated to OpenVMS.

Knowing nothing, I'd guess that
"RESERVED_MEMORY" and "permanently allocated
to OpenVMS" might not be the same things.

Re: Memory permanently allocated to OpenVMS

Kevin Carter_3 — Mon, 09 Aug 2010 19:27:12 GMT

Steven,
Just curious; if you do a
$ set process/units=bytes
$ show memo
what is the result?

Re: Memory permanently allocated to OpenVMS

Steven Schweda — Mon, 09 Aug 2010 20:26:21 GMT

> $ set process/units=bytes

Too sticky, but I'll do this:

ALP $ show memo /unit = byte
System Memory Resources on 9-AUG-2010 16:23:48.80

Physical Memory Usage (bytes): Total Free In Use Modified
Main Memory (GB) 2.00 0.57 1.39 0.03

Extended File Cache (Time of last reset: 19-JUN-2010 07:22:55.69)
Allocated (MBytes) 103.03 Maximum size (MBytes) 1024.00
Free (MBytes) 0.01 Minimum size (MBytes) 3.12
In use (MBytes) 103.01 Percentage Read I/Os 95%
Read hit rate 71% Write hit rate 0%
Read I/O count 25521866 Write I/O count 1227702
Read hit count 18358474 Write hit count 0
Reads bypassing cache 286 Writes bypassing cache 243
Files cached open 994 Files cached closed 2131
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 (bytes): Total Free In Use Released
Execlet code region (MB) 12.00 0.00 10.84 1.15
Execlet data region (MB) 8.00 0.00 3.81 4.17
S0S1 Exec data region (MB) 13.01 0.00 13.01 0.00
S0S1 Resident image code (MB) 16.00 0.00 9.48 6.51

Slot Usage (slots): Total Free Resident Swapped
Process Entry Slots 1024 885 114 25
Balance Set Slots 1022 885 112 25

Dynamic Memory Usage: Total Free In Use Largest
Nonpaged Dynamic Memory (MB) 23.20 14.98 8.21 0.41
Bus Addressable Memory (KB) 128.00 110.87 17.12 104.00
Paged Dynamic Memory (MB) 7.84 5.05 2.78 4.95
Lock Manager Dyn Memory (MB) 4.84 1.42 3.41

Buffer Object Usage (bytes): In Use Peak
32-bit System Space Windows (S0/S1) (MB) 16.17 16.26
64bit System Space Windows (S2) (MB) 1.09 1.56
Physical bytes locked by buffer objects (MB) 17.27 17.35

Memory Reservations (bytes): Group Reserved In Use Type
Total (0 bytes reserved) 0 0

Swap File Usage (bytes): Index Free Size
DISK$VMS083ALP:[SYS0.SYSEXE]SWAPFILE.SYS
(MB) 1 51.93 64.43

Paging File Usage (bytes): Index Free Size
DISK$VMS083ALP:[000000]PAGEFILE.SYS;6
(GB) 253 1.92 3.05
DISK$VMS083ALP:[SYS0.SYSEXE]PAGEFILE.SYS
(GB) 254 0.43 1.56

Total size of all paging files: (GB) 4.61
Total committed paging file usage:(GB) 3.35

Of the physical memory in use, 84.93 MB are permanently allocated to OpenVMS.
ALP $

Re: Memory permanently allocated to OpenVMS

John Gillings — Mon, 09 Aug 2010 20:32:27 GMT

KC,

>Steven,
>Just curious

We're supposed to be asking you for output, not the other way around ;-)

Usually such an apparently large chunk of memory would be reserved for something like an Oracle SGA. Depending on what version of Oracle you're running (if any), there are different ways that it could be reserved. My guess is you have a bigger data base on the system showing a higher permanent allocation.

Could you please post your output from SHOW MEMORY. Something else which might be interesting:

$ PIPE INSTALL LIST/GLOBAL | SEARCH/WINDOW=(0,1) SYS$PIPE ORA

Re: Memory permanently allocated to OpenVMS

Kevin Carter_3 — Mon, 09 Aug 2010 21:34:26 GMT

show mem
System Memory Resources on 9-AUG-2010 15:26:28.78

Physical Memory Usage (bytes): Total Free In Use Modified
Main Memory (GB) 4.00 0.66 2.94 0.39

Extended File Cache (Time of last reset: 30-JUL-2010 13:39:36.62)
Allocated (MBytes) 49.07 Maximum size (MBytes) 2048.00
Free (MBytes) 0.00 Minimum size (MBytes) 3.12
In use (MBytes) 49.07 Percentage Read I/Os 85%
Read hit rate 98% Write hit rate 0%
Read I/O count 40817039 Write I/O count 6798650
Read hit count 40195968 Write hit count 0
Reads bypassing cache 406069 Writes bypassing cache 4508352
Files cached open 654 Files cached closed 555
Vols in Full XFC mode 0 Vols in VIOC Compatible mode 3
Vols in No Caching mode 1 Vols in Perm. No Caching mode 0

Granularity Hint Regions (bytes): Total Free In Use Released
Execlet code region (MB) 12.00 0.00 11.71 0.28
Execlet data region (MB) 4.00 0.00 3.80 0.19
S0S1 Exec data region (MB) 8.63 0.00 8.63 0.00
S0S1 Resident image code (MB) 16.00 0.00 9.48 6.51

Slot Usage (slots): Total Free Resident Swapped
Process Entry Slots 146 41 105 0
Balance Set Slots 144 41 103 0

Dynamic Memory Usage: Total Free In Use Largest
Nonpaged Dynamic Memory (MB) 9.56 3.79 5.76 0.08
Paged Dynamic Memory (MB) 2.56 0.79 1.77 0.76
Lock Manager Dyn Memory (KB) 944.00 120.75 823.25

Buffer Object Usage (bytes): In Use Peak
32-bit System Space Windows (S0/S1) (KB) 56.00 64.00
64bit System Space Windows (S2) (bytes) 0.00 0.00
Physical bytes locked by buffer objects (KB) 56.00 64.00

Memory Reservations (bytes): Group Reserved In Use Type
Total (0 bytes reserved) 0 0

Write Bitmap (WBM) Memory Summary
Local bitmap count: 0 Local bitmap memory usage (bytes) 0.00
Master bitmap count: 4 Master bitmap memory usage (KB) 328.00

Swap File Usage (bytes): Index Free Size
DISK$ALPHASYS:[SYS0.SYSEXE]SWAPFILE.SYS
(MB) 1 10.87 10.87

Paging File Usage (bytes): Index Free Size
DISK$ALPHASYS:[SYS0.SYSEXE]PAGEFILE.SYS
(MB) 254 446.10 488.25
Total committed paging file usage:(GB) 1.48

Of the physical memory in use, 2.22 GB are permanently allocated to OpenVMS.

PIPE INSTALL LIST/GLOBAL | SEARCH/WINDOW=(0,1) SYS$PIPE ORA
ORA_DEV_SGA (00000000) WRT DZRO TMP SYS Pgltcnt/Refcnt=1912
928/2391160
Memory Resident Shared Page Tables: Pgltcnt/Refcnt=1872/2341
***************
ORA_TST_SGA (00000000) WRT DZRO TMP SYS Pgltcnt/Refcnt=2584
672/4200092
Memory Resident Shared Page Tables: Pgltcnt/Refcnt=2528/4109
***************
DSA30:ora_java_vms_shr.EXE
INS$8570ACD0_004(01000001) PRM SYS Pgltcnt/Refcnt=111/
0
INS$8570ACD0_003(01000001) PRM SYS Pgltcnt/Refcnt=7/0
***************
DSA30:ORACLE.EXE
INS$8570A0A0_003(0E35C7ED) PRM SYS Pgltcnt/Refcnt=1842
54/529736
DSA0:DECW$AILSHR_TV_SUPPORT.EXE
INS$85709B40_004(0100000E) PRM SYS Pgltcnt/Refcnt=79/0
***************
DSA30:libclntsh.SO
INS$85709030_004(0A000002) PRM SYS Pgltcnt/Refcnt=3294
3/0
INS$85709030_003(0A000002) PRM SYS Pgltcnt/Refcnt=1801
/0

Re: Memory permanently allocated to OpenVMS

John Gillings — Mon, 09 Aug 2010 22:59:39 GMT

KC,

Well there's you're answer...

Your DEV data base SGA is 1912928, pagelets =934MB and TST is 2584672 pagelets =1262MB

Together that's 2.14GB, so your Memory permanently allocated to OpenVMS ignoring Oracle is 0.08GB, which seems perfectly reasonable (indeed, it's very close to the value from Steven's non-Oracle system).

Compare the same command on your other system. Chances are its SGAs add up to about 1.41GB, leaving around the same memory usage as the other system.

"seems a little excessive" - talk to your DBA. Presumably you bought the 4GB of memory for Oracle to use, and that's what it's doing.

QED

Re: Memory permanently allocated to OpenVMS

Kevin Carter_3 — Mon, 09 Aug 2010 23:13:29 GMT

John,
Thanks for the info! I had no idea that memory allocated to Oracle would show up as part of memory "permanently allocated...".
KC