Viewstore Database Re-organisation Benchmarks
The benchmarks comprise a re-organise of a ViewStore database of 7,900
records reducing it to 7,048 records, each record being allocated 5 bytes of
free space for future amendment. The re-organisation comprises three steps :-
1) SELECT - Creates a list of records required in the new database.
2) CONVERT - Creates the new database from the list produced at 1.
3) INDEX - Creates the index for the new database.
The original database size was &56776 (354,166) bytes with an average
record length of 45 bytes. The revised database size was &4A719 (304,921) bytes
with an average record length of 44 bytes. The resulting index size was &4C001
(311,297) bytes.
These benchmarks were run via exec files in order to prevent human
response times from influencing the figures.
Start End Duration
Description HH:MM:SS HH:MM:SS HH:MM:SS
Master 128 + ADFS 1.50 + Floppies SELECT 21:00:06 21:12:43 00:12:37
CONVERT 21:12:43 21:47:03 00:34:20
INDEX 21:48:41 00:42:01 02:53:20
Total 03:40:17
Master 128 + ADFS 2.03 + Floppies SELECT 14:40:44 14:53:31 00:12:47
CONVERT 14:53:31 15:27:12 00:33:41
INDEX 15:29:33 18:24:52 02:55:19
Total 03:41:47
Master 128 Turbo + ADFS 2.03 + Floppies SELECT 02:49:16 03:01:40 00:12:24
CONVERT 03:01:40 03:34:59 00:33:19
INDEX 03:37:21 06:35:59 02:58:38
Total 03:44:21
-----------------------------------------------------------------------------
Master 128 + ADFS 1.50 + Syquest SELECT 22:58:53 23:05:39 00:06:46
CONVERT 23:05:39 23:15:33 00:09:54
INDEX 23:15:33 23:45:10 00:29:37
Total 00:46:17
Master 128 + ADFS 2.03 + Syquest SELECT 18:26:40 18:33:25 00:06:45
CONVERT 18:33:25 18:43:16 00:09:41
INDEX 18:43:17 19:12:28 00:29:11
Total 00:45:37
Master 128 Turbo + ADFS 2.03 + Syquest SELECT 01:28:49 01:35:07 00:06:18
CONVERT 01:35:07 01:44:42 00:09:35
INDEX 02:44:42 02:13:59 00:29:17
Total 00:45:10
-----------------------------------------------------------------------------
Master 128 + CPFS SELECT 01:23:29 01:29:43 00:06:14
CONVERT 01:29:43 01:39:30 00:09:47
INDEX 01:39:30 01:47:33 00:08:03
Total 00:24:04
-----------------------------------------------------------------------------
The above figures illustrate that the limiting factor on performance
of the re-organisation process is the speed of the device on which the database
resides. The Alternate Master Rom version of ADFS(2.03), whilst it
significantly improves the sequential reading of the database, gives a slightly
poorer response on floppy disks for the re-org, but a marginal improvement on
the hard disk. It must be noted, however, that the floppy drives were not
subjected to as much 'stopping & starting' as with the standard ADFS (1.50),
the floppy drives making far less noise! Unfortunately, this did not improve
the response times!
Use of a second processor, or in this case the 'Turbo' board, gives
only 1,536 bytes more Ram for ViewStore over that available on a standard
Master 128, as ViewStore does not have a 'High' version. Obviously, the
difference would be greater if a BBC Model 'B' was used as the base machine.
The combination of extra Ram and faster processor does very little to improve
the performance of ViewStore in the re-org. Note that for complex report
generation, the extra Ram and increased processor speed does make some
difference.
The most significant speed improvement is gained by eliminating the
mechanical aspects of floppy/hard disk drives. This was achieved by means of
the Acorn 512 board (expanded to 1Meg) and Essential Software's CPFS
(Co-Processor Filing System). This turns the 512 board into a RAM disk, with no
moving parts. Obviously, the operations that use the disk the heaviest will
show the most significant speed improvement. Thus it was the building of the
index that went from just under 3 hours on floppies, to just under 30 minutes
on the hard disk, finally to just over 8 minutes on CPFS. This gives the hard
disk a speed improvement of 600% over floppies, and CPFS a speed improvement of
360% improvement over the hard disk and a massive 2100% over floppies!
S Richardson K2O