Independant AFS FAQ - DiskSpeed Results

AFS FAQ
DiskSpeed Results
Last updated 23-February-1997

Copyright © 1996-1997 Mark Harden - All rights reserved.
Please do not copy. Make a link. That way we have one up to date copy !
E-Mail : faq@harden.demon.co.uk

SetUp

    Computer    = A4000/040 25 MHz      Disk Drive  = WDC AC31600H
    OS          = 3.1 (40.70)           MaxTransfer = 0x1FE00
    AFS         = 2.4 (16.20)           DMAMask     = 0x7FFFFFFC
    FFS         = 3.1 (40.1)            Buffers     = 200
    Tester      = DiskSpeed 4.0

Directory manipulation speed

                       FFS             AFS
Function            xPS   CPU       xPS   CPU      IMPROVEMENT
--------------------------------------------------------------
File Create:        125 |  93%      146 |  97%       +   17%
File Open:          141 |  82%      203 | 100%       +   44%
Directory Scan:     516 |  96%     1639 | 100%       +  218%
File Delete:        407 |  95%      243 | 100%       -   40%

Seek/Read:         1066 |  93%      398 |  57%       -   63%

Testing with a 512 byte buffer.  (LONG-aligned, MEMF_FAST)

Create file:     261946 |  99%   386138 | 100%       +   47%
Write to file:   296181 | 100%   472640 | 100%       +   60%
Read from file:  288695 |  92%   258304 |  99%       -   11%

Testing with a 4096 byte buffer.  (LONG-aligned, MEMF_FAST)

Create file:     839680 |  82%   751616 | 100%      -   11%
Write to file:  1136128 |  97%   818688 | 100%      -   28%
Read from file:  785450 |  73%  1025024 |  96%      +   31%

Testing with a 32768 byte buffer.  (LONG-aligned, MEMF_FAST)

Create file:     880816 |  55%  1757184 |  98%      +   99%
Write to file:  1232896 |  66%  1914534 |  97%      +   55%
Read from file: 1034994 |  68%  1507328 |  94%      +   46%

Testing with a 262144 byte buffer.  (LONG-aligned, MEMF_FAST)

Create file:    1652576 |  88%  1799990 |  97%      +    9%
Write to file:  1856174 |  86%  2094533 |  75%      +   13%
Read from file: 1485052 |  87%  1612201 |  93%      +    9%

Testing with a 512 byte buffer.  (WORD-aligned, MEMF_FAST)

Create file:     260352 |  98%   377616 | 100%      +   45%
Write to file:   293531 |  99%   458765 | 100%      +   56%
Read from file:  287644 |  92%   250052 |  99%      -   13%

Testing with a 4096 byte buffer.  (WORD-aligned, MEMF_FAST)

Create file:     851415 |  83%   737280 | 100%      -   13%
Write to file:  1121792 |  97%   802816 | 100%      -   28%
Read from file:  782336 |  72%  1026048 |  96%      +   31%

Testing with a 32768 byte buffer.  (WORD-aligned, MEMF_FAST)

Create file:     881904 |  56%  1750899 |  99%      +   99%
Write to file:  1227265 |  67%  1894080 |  97%      +   54%
Read from file: 1033703 |  67%  1509537 |  93%      +   46%

Testing with a 262144 byte buffer.  (WORD-aligned, MEMF_FAST)

Create file:    1638400 |  88%  1788823 |  97%      +    9%
Write to file:  1853871 |  86%  2106224 |  97%      +   13%
Read from file: 1492403 |  86%  1610221 |  92%      +    8%

Testing with a 512 byte buffer.  (BYTE-aligned, MEMF_FAST)

Create file:     224719 |  87%   324288 | 100%      +   44%
Write to file:    52727 |  34%   384768 | 100%      +  630%
Read from file:  242883 |  98%   225059 |  99%      -    7%

Testing with a 4096 byte buffer.  (BYTE-aligned, MEMF_FAST)

Create file:     318856 |  85%   736256 |  99%      +  131%
Write to file:    62393 |  31%   806400 | 100%      + 1192%
Read from file:  285125 |  82%   778752 |  98%      +  173%

Testing with a 32768 byte buffer.  (BYTE-aligned, MEMF_FAST)

Create file:     287964 |  73%  1133175 |  99%      +  294%
Write to file:    52864 |  26%  1213478 | 100%      + 2195%
Read from file:  256127 |  69%  1029617 |  96%      +  302%

Testing with a 262144 byte buffer.  (BYTE-aligned, MEMF_FAST)

Create file:     293850 |  73%  1201899 |  98%      +  309%
Write to file:    50499 |  25%  1333486 |  97%      + 2541%
Read from file:  227922 |  62%  1120273 |  95%      +  392%

Note that the WORD and LONG results are basically the same. You can see that AFS is faster than FFS more often than not. You can also see that AFS uses more CPU time than FFS. This is deceptive. If you play with the figures you will deduce that for a certain transfer AFS will use a lot of CPU for a short time. FFS would use less for longer. The overall effect is the same.