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Conference bulova::decw_jan-89_to_nov-90

Title:DECWINDOWS 26-JAN-89 to 29-NOV-90
Notice:See 1639.0 for VMS V5.3 kit; 2043.0 for 5.4 IFT kit
Moderator:STAR::VATNE
Created:Mon Oct 30 1989
Last Modified:Mon Dec 31 1990
Last Successful Update:Fri Jun 06 1997
Number of topics:3726
Total number of notes:19516

427.0. "Pagefile Fragmentation" by FUTURA::MCNULTY (Earth: The hostess, not the meal.) Fri Mar 17 1989 09:35

I'm having an ongoing problem with pagefile fragmentation. Several times I've 
ended up with the dreaded "Page file space critical, system trying to continue"
followed by the system hanging. I had been tuning my system only with Autogen. 

Based on an article in the 20-FEB-1989 Digital Review, I boosted my FREELIM, 
FREEGOAL, MPW_HILIMIT and a few other parameters to increase the size of my
Free Page List and Modified Page List. This seemed to help, but I still have
the fragmentation problem. 

The system is:

			VSII, mono., 16Meg
			VMS and DECWindows SDC 5.1
			2 RD54's, one TK drive


 $ SHO MEM
             System Memory Resources on 17-MAR-1989 09:22:26.87

Physical Memory Usage (pages):     Total        Free      In Use    Modified
  Main Memory (16.00Mb)            32768        3424       28930         414

Slot Usage (slots):                Total        Free    Resident     Swapped
  Process Entry Slots                 41          12          29           0
  Balance Set Slots                   36           9          27           0

Fixed-Size Pool Areas (packets):   Total        Free      In Use        Size
  Small Packet (SRP) List            656         157         499          96
  I/O Request Packet (IRP) List      273          89         184         176
  Large Packet (LRP) List             41          20          21        1648

Dynamic Memory Usage (bytes):      Total        Free      In Use     Largest
  Nonpaged Dynamic Memory         575488       36240      539248       27872
  Paged Dynamic Memory            274432       90480      183952       89488

Paging File Usage (pages):                      Free  Reservable       Total
  DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS      30000       30000       30000
  DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS       2463      -44188       19992

Of the physical pages in use, 4079 pages are permanently allocated to VMS.


This is while running my standard bunch of DECWindows stuff: Three DECterms, 
one VUE, Calendar, Cardfiler, DECWindows MAIL, and DECWindows NOTES. I am the 
only user on the system. My process parameters are:

Maxjobs:         0  Fillm:       100  Bytlm:        60000
Maxacctjobs:     0  Shrfillm:      0  Pbytlm:           0
Maxdetach:       0  BIOlm:        18  JTquota:       1024
Prclm:          25  DIOlm:        18  WSdef:          256
Prio:            4  ASTlm:        24  WSquo:          512
Queprio:         0  TQElm:        20  WSextent:     10000
CPU:        (none)  Enqlm:       200  Pgflquo:      45000

I tried running a secondary pagefile on the user disk, but that didn't seem to
make any difference. DUA0 has about 16,000 blocks free. I know that's a bit tight,
I'm looking to see what else I can move off to the other disk. 

So, am I just trying to run too much at once? Is anyone else having a problem
with fragmentation? Any suggestions? I'll be happy to supply any other required 
information.



				Lance

T.RTitleUserPersonal
Name
DateLines
427.1QUARK::LIONELThe dream is aliveFri Mar 17 1989 10:0212
A 20,000 block pagefile is FAR too small for a 16MB system.  On my 13MB
system I am using 70K blocks right now.  I was also successful with two
50K block files on two separate disks, though I think that's a bit much.

I suggest boosting your pagefile size to 50K blocks at least, and get rid
of the swapfile - you're just wasting disk space with it.

Also, I believe that the "page file fragmented" message may come out if one
of the files is full, even if you have another one that is empty.

			Steve

427.2Need more PAGEFILERAMBLR::MORONEYAnything's legal as long as you don't get caughtFri Mar 17 1989 10:1512
You're running AUTOGEN yet you still have a 30,000 block swapfile?  Betcha you
have SWAPFILE=0 and probably PAGEFILE=0 in your MODPARAMS.DAT.  Take these
lines out for now.  I have a 1200 block SWAPFILE.

Basically, your problem is your pagefile is too small.  DECWindows really eats
up virtual memory.  Free up lots of room on your system disk (AUTOGEN will need
room to create a bigger PAGEFILE), remove any SWAPFILE=xxx or PAGEFILE=xxx in
your MODPARAMS.DAT and run AUTOGEN. Remember to purge old SWAPFILEs/PAGEFILEs
after AUTOGENning/rebooting.

-Mike

427.3STAR::MFOLEYRebel without a ClueFri Mar 17 1989 11:055
	And remember to use the FEEDBACK option with Autogen!

						mike

427.4STAR::KAPLANRunning w/the blade guards disengaged.Tue Mar 21 1989 07:2112
    
    When expanding your PAGEFILE it is often useful to keep it contiguous.
    
    I believe its much more important to have the first have contiguous (or
    near contiguous) -- it have to do with the algorithms that generate the
    fragmentation message(s) to the console.
    
    If you find your disk is too full, you'll probably have to use backup
    to defragment your disk.
    
    -jck

427.5LESLIE::LESLIEAndy ��� LeslieTue Mar 21 1989 08:388
    re: .4 As Steve said in .1, this problem is certainly due to the small
    size pagefile. 
    
    Don't confuse Pagefile fragmentation with disk fragmentation - they
    differ.
    
    Andy

427.6I'm trying a bigger oneFUTURA::MCNULTYEarth: The hostess, not the meal.Tue Mar 21 1989 15:5111
Thanks for the replies.

I was using AUTOGEN with feedback. It was trying to make my pagefile *smaller*!
I did a ruthless housecleaning and cleared up a bunch of space on my user disk.
I did a backup/restore of that disk, and created a contiguous 60k secondary
pagefile. I'll see how it goes.



				Lance

427.7Still not fixedFUTURA::MCNULTYEarth: The hostess, not the meal.Wed Mar 22 1989 11:1433
That didn't take long. I just got the "Page file space critical, system trying 
to continue." message. All my info is the same as in the basenote except my 
pagefile setup is now:


Physical Memory Usage (pages):     Total        Free      In Use    Modified
  Main Memory (16.00Mb)            32768        4373       28092         303

Slot Usage (slots):                Total        Free    Resident     Swapped
  Process Entry Slots                 41          12          29           0
  Balance Set Slots                   36           9          27           0

Fixed-Size Pool Areas (packets):   Total        Free      In Use        Size
  Small Packet (SRP) List            570          71         499          96
  I/O Request Packet (IRP) List      273          91         182         176
  Large Packet (LRP) List             43          22          21        1648

Dynamic Memory Usage (bytes):      Total        Free      In Use     Largest
  Nonpaged Dynamic Memory         575488       32992      542496       23856
  Paged Dynamic Memory            274432       90128      184304       89232

Paging File Usage (pages):                      Free  Reservable       Total
  DISK$MICROVMS:[SYS0.SYSEXE]SWAPFILE.SYS      30000       30000       30000
  DISK$MICROVMS:[SYS0.SYSEXE]PAGEFILE.SYS       1342         -34        1896
  FUTURA$DISK2:[SECONDARY]PAGEFILE1.SYS;1      43937       -2345       59992
  

Any other suggestions/ideas are most welcome. Should I just make the pagefile
still bigger? (Heck, I didn't need to keep any _files_ on this RD54 anyway ;^)


				Lance

427.8Don't need it that big in V5STAR::MFOLEYRebel without a ClueWed Mar 22 1989 11:168

	Why have a 30k swapfile? I highly doubt you need one that big!
	Swap the sizes of your primary page and swap files. and
	see how you do..

							mike

427.9STAR::MFOLEYRebel without a ClueWed Mar 22 1989 11:186

	Also, are you using AUTOGEN with Feedback???

						mike

427.10QUARK::LIONELThe dream is aliveWed Mar 22 1989 12:206
Get rid of the 1900 block pagefile.  That's causing most of your problems.
And I agree - you don't need a 30K block swapfile!  You probably don't need
one at all, but 5000 blocks tops!

			Steve

427.11Another shot in the darkAGBEAR::HORNERA.G.Bear, Low tech teddy bearWed Mar 22 1989 12:2517
    Please don't yell if I don't have this quite right, but...

    We had a similiar problem with a small primary page file and a much
    larger secondary page file.  It seems that some of the VMS processes
    get assigned to whatever page file is available at the time that
    they start, and this vastly overcommited the primary file.  We were
    mounting the secondary pagefile disk and installing the secondary
    pagefile in our SYSTARTUP_V5 file which was too late in the startup
    process.  We moved the mounting of disks and installing of the
    secondary pagefile into SYPAGSWPFILES.COM which is executed far
    earlier in the startup process.  This made a tremendous difference
    as it seemed to be early enough that the VMS processes were allowed
    to use the larger secondary file.  Our problem completely disappeared
    after doing this.

                 Dave

427.12QUARK::LIONELThe dream is aliveWed Mar 22 1989 13:1610
Re: .11

The situation you describe was correct for V4, but not V5.  In V5, processes
can move around between pagefiles and even can use more than one.  Also,
allocation is now made on the basis of percent full rather than absolute
space.  So it is now best to have either one big file or multiple files of
similar sizes.  Having vastly dissimilar sizes will cause trouble.

			Steve