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Blocksize question
Message
De
23/07/2002 11:56:04
Hilmar Zonneveld
Independent Consultant
Cochabamba, Bolivie
 
 
À
23/07/2002 11:50:43
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00681544
Message ID:
00681729
Vues:
12
>Hi Hilmar.
>
>>Is there a performance cost if I set the blocksize in the memo to a single byte?
>
>As usual, you'll have to test under your specific conditions to determine this. However, in testing I did several years ago, I was surprised to find no performance difference in using a blocksize of 1. I think the reason is that VFP internally reads and caches blocks of data and doesn't really read it from the file in blocksize increments.
>
>Doug

Thanks.

Well, I thought there might be a performance hit from other sources - like (perhaps) VFP taking longer to find unused space to save a memo field, or (again perhaps) a slightly greater probability of having to read data from more than one sector from disk. I understand that the operating system (or the disk system?) reads an entire sector at a time.

Hilmar.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
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