[comp.os.vms] TPU virtual memory loss problem

gregg@a.cs.okstate.edu (Gregg Wonderly) (05/20/87)

There is an easy solution to this problem.  It appears that TPU attempts to
speed allocation and deallocation of data by waiting until procedure exit
to clean house.  I have included the output from 2 different runs of the
posted procedure with the second having one modification.  I moved the
lines:

        ERASE(CREATE_RANGE(MARK(NONE),MARK(NONE),NONE));
        COPY_TEXT(S);

into a procedure by themselves.  The result was that the test procedure ran
to completion in just under 3 minutes, instead of 22 hours.  And, there where
only 647 page faults instead of 47 million.  Needless to say, I am unimpressed
with this type of difference in performance.

Now off to look at search and replace in EVE, maybe there is a speed up there.

----------------------  First run  ------------------------

  Date and Time          Iterations      I/O       CPU       Page flts Ph.Mem
15-MAY-1987 11:16:39.31           1      159   0 00:00:23.81       708    655
15-MAY-1987 11:17:58.33           2      164   0 00:01:18.13       801    681
15-MAY-1987 11:19:44.63           3      166   0 00:02:48.94       897    713
15-MAY-1987 11:22:00.17           4      168   0 00:04:51.27       986    802
15-MAY-1987 11:25:03.40           5      170   0 00:07:27.85      1092    886
15-MAY-1987 11:28:47.53           6      172   0 00:10:38.18      1181    975
15-MAY-1987 11:33:08.68           7      174   0 00:14:24.07      1277   1064
15-MAY-1987 11:38:38.51           8      176   0 00:18:43.41      1366   1153
15-MAY-1987 11:44:54.10           9      178   0 00:23:37.95      1467   1242
15-MAY-1987 11:51:18.62          10      180   0 00:29:05.20      1565   1333
15-MAY-1987 11:58:19.01          11      182   0 00:35:07.12      1654   1422
15-MAY-1987 12:06:13.90          12      184   0 00:41:42.55      1750   1511
15-MAY-1987 12:15:14.66          13      186   0 00:48:53.89      1886   1583
15-MAY-1987 12:27:00.47          14      188   0 00:56:38.74      1979   1607
15-MAY-1987 12:37:13.19          15      190   0 01:04:55.83      2074   1607
15-MAY-1987 12:48:32.26          16      192   0 01:13:49.03      2169   1701
15-MAY-1987 12:59:17.88          17      194   0 01:23:14.24      2257   1789
15-MAY-1987 13:10:34.46          18      196   0 01:33:13.07      2353   1879
15-MAY-1987 13:23:35.55          19      198   0 01:43:51.79      2450   1969
15-MAY-1987 13:37:19.24          20      200   0 01:55:00.61      2540   2059
15-MAY-1987 13:59:25.96          21      202   0 02:06:51.60     10496   1845
15-MAY-1987 14:18:16.82          22      204   0 02:19:15.74     18157   1915
15-MAY-1987 14:40:53.10          23      206   0 02:32:20.31     36568   2036
15-MAY-1987 15:03:25.44          24      208   0 02:46:23.64     61633   2071
15-MAY-1987 15:22:14.02          25      210   0 03:00:50.16     68910    500
15-MAY-1987 15:42:27.31          26      212   0 03:15:41.13     88509   2234
15-MAY-1987 16:08:38.95          27      214   0 03:31:49.61    188868   2321
15-MAY-1987 16:54:31.61          28      216   0 03:50:56.84    488930   2443
15-MAY-1987 17:13:43.33          29      218   0 04:07:13.87    491327   2600
15-MAY-1987 17:33:44.40          30      220   0 04:24:06.95    497713   2566
15-MAY-1987 18:02:29.98          31      222   0 04:43:05.31    654311   2600
15-MAY-1987 18:51:09.28          32      224   0 05:13:04.77   1809859   2600
15-MAY-1987 20:06:02.67          33      226   0 05:49:45.30   3555137   2600
15-MAY-1987 21:09:43.71          34      228   0 06:26:33.18   5292352   2600
15-MAY-1987 21:49:36.01          35      230   0 07:00:18.75   6735915   2600
15-MAY-1987 22:35:25.70          36      232   0 07:39:32.16   8670622    500
15-MAY-1987 23:33:06.10          37      234   0 08:29:55.22  11704326   2600
16-MAY-1987 00:18:27.39          38      236   0 09:08:10.09  13424848   2600
16-MAY-1987 01:21:06.63          39      238   0 09:53:27.92  15779785   2600
16-MAY-1987 02:20:27.18          40      240   0 10:40:09.90  18134344   2600
16-MAY-1987 03:33:17.20          41      242   0 11:35:53.09  21332083   2450
16-MAY-1987 04:49:48.76          42      244   0 12:33:32.74  24603502    500
16-MAY-1987 06:02:35.12          43      246   0 13:33:02.47  28088420    500
16-MAY-1987 07:24:34.83          44      248   0 14:33:54.77  31633838   2052
16-MAY-1987 09:13:44.16          45      250   0 15:38:53.22  35188094   2600
16-MAY-1987 12:01:10.77          46      252   0 16:52:32.98  37615322   1731
16-MAY-1987 15:20:52.03          47      254   0 18:09:44.60  39604420   1548
16-MAY-1987 19:47:04.20          48      256   0 19:32:14.77  40230435   1044
16-MAY-1987 22:12:48.63          49      258   0 20:45:51.36  43498464   2598
16-MAY-1987 23:54:43.31          50      260   0 21:58:35.06  47498545   2599

--------------------------   differences output   -----------------------------

************
File MATH$STAFF:[GREGG]TRY1.COM;2
   26   				ERASE(CREATE_RANGE(MARK(NONE),MARK(NONE),NONE));
   27   				COPY_TEXT(S);
   28   			ENDLOOP;
******
File MATH$STAFF:[GREGG]TRY.COM;3
   26   				do_func(s);
   27   			ENDLOOP;
************
************
File MATH$STAFF:[GREGG]TRY1.COM;2
   32   GROW
******
File MATH$STAFF:[GREGG]TRY.COM;3
   31   
   32   PROCEDURE do_func (s)
   33   	ERASE(CREATE_RANGE(MARK(NONE),MARK(NONE),NONE));
   34   	COPY_TEXT(S);
   35   ENDPROCEDURE;
   36   
   37   GROW
************

Number of difference sections found: 2
Number of difference records found: 8

DIFFERENCES /IGNORE=()/MERGED=1/OUTPUT=TRY.DIFF;1-
    TRY1.COM;2-
    TRY.COM;3

------------------------------  Second run after change   ---------------------

  Date and Time          Iterations      I/O       CPU       Page flts Ph.Mem
18-MAY-1987 15:28:24.62           0      160   0 00:00:04.25       623    546
18-MAY-1987 15:31:16.63           1      162   0 00:00:07.02       645    568
18-MAY-1987 15:33:35.40           2      164   0 00:00:09.76       645    568
18-MAY-1987 15:37:33.33           3      166   0 00:00:12.57       645    568
18-MAY-1987 15:40:52.12           4      168   0 00:00:15.43       645    568
18-MAY-1987 15:43:34.04           5      170   0 00:00:18.28       645    568
18-MAY-1987 15:46:15.55           6      172   0 00:00:21.18       645    568
18-MAY-1987 15:49:08.48           7      174   0 00:00:24.12       645    568
18-MAY-1987 15:51:20.45           8      176   0 00:00:27.06       645    568
18-MAY-1987 15:54:18.05           9      178   0 00:00:30.05       645    568
18-MAY-1987 15:56:51.20          10      180   0 00:00:33.06       645    568
18-MAY-1987 16:01:38.81          11      182   0 00:00:36.08       645    568
18-MAY-1987 16:06:23.36          12      184   0 00:00:39.20       645    568
18-MAY-1987 16:08:51.35          13      186   0 00:00:42.29       645    568
18-MAY-1987 16:11:13.13          14      188   0 00:00:45.43       645    568
18-MAY-1987 16:13:20.41          15      190   0 00:00:48.60       645    568
18-MAY-1987 16:15:26.15          16      192   0 00:00:51.82       645    568
18-MAY-1987 16:18:02.51          17      194   0 00:00:55.11       645    568
18-MAY-1987 16:20:30.74          18      196   0 00:00:58.36       645    568
18-MAY-1987 16:22:59.25          19      198   0 00:01:01.64       645    568
18-MAY-1987 16:25:34.95          20      200   0 00:01:04.97       645    568
18-MAY-1987 16:28:46.99          21      202   0 00:01:08.36       645    568
18-MAY-1987 16:31:55.58          22      204   0 00:01:11.79       645    568
18-MAY-1987 16:34:39.66          23      206   0 00:01:15.23       645    568
18-MAY-1987 16:37:00.94          24      208   0 00:01:18.71       645    568
18-MAY-1987 16:39:45.06          25      210   0 00:01:22.25       645    568
18-MAY-1987 16:42:13.66          26      212   0 00:01:25.80       645    568
18-MAY-1987 16:44:04.34          27      214   0 00:01:29.35       645    568
18-MAY-1987 16:46:33.19          28      216   0 00:01:32.94       645    568
18-MAY-1987 16:49:01.96          29      218   0 00:01:36.54       645    568
18-MAY-1987 16:51:08.91          30      220   0 00:01:40.17       645    568
18-MAY-1987 16:54:37.04          31      222   0 00:01:43.81       645    568
18-MAY-1987 16:57:11.75          32      224   0 00:01:47.50       645    568
18-MAY-1987 17:00:09.49          33      226   0 00:01:51.26       645    568
18-MAY-1987 17:02:45.31          34      228   0 00:01:55.03       645    568
18-MAY-1987 17:05:06.61          35      230   0 00:01:58.81       645    568
18-MAY-1987 17:07:20.04          36      232   0 00:02:02.67       645    568
18-MAY-1987 17:09:55.10          37      234   0 00:02:06.51       645    568
18-MAY-1987 17:12:39.15          38      236   0 00:02:10.37       645    568
18-MAY-1987 17:15:08.99          39      238   0 00:02:14.31       645    568
18-MAY-1987 17:17:39.07          40      240   0 00:02:18.24       645    568
18-MAY-1987 17:20:14.21          41      242   0 00:02:22.26       646    569
18-MAY-1987 17:23:26.19          42      244   0 00:02:26.31       646    569
18-MAY-1987 17:26:09.78          43      246   0 00:02:30.36       646    569
18-MAY-1987 17:28:30.65          44      248   0 00:02:34.48       646    569
18-MAY-1987 17:30:50.96          45      250   0 00:02:38.60       647    570
18-MAY-1987 17:33:28.37          46      252   0 00:02:42.72       647    570
18-MAY-1987 17:36:00.95          47      254   0 00:02:46.90       647    570
18-MAY-1987 17:39:45.49          48      256   0 00:02:51.08       647    570
18-MAY-1987 17:42:51.45          49      258   0 00:02:55.33       647    570
18-MAY-1987 17:46:10.70          50      260   0 00:02:59.64       647    570