+#LyX 1.3 created this file. For more info see http://www.lyx.org/
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+\layout Title
+
+Comparacion de Tipo de archivos.
+\layout Standard
+
+Método utilizado para la comparación
+\layout Standard
+
+Para realizar la comparación entre los distintos tipos de archivo, se generaron
+ un xml de articulos con 200 entradas y uno de facturas de 1750 entreadas.
+ Los valores fueron arbitrarios y un poco mas elevados que los requeridos
+ en el enunciado para poner a prueba el sistema.
+\layout Standard
+
+En la tabla que se dará más adelante, se pueden apreciar los datos característic
+os de cada tipo de archivo.
+ El métido de prueba fue el siguiente :
+\layout Enumerate
+
+Para cada tipo de archivo se cargaron los archivos xml de prueba
+\layout Enumerate
+
+Se anotaron las estadísticas que entrega la GUI
+\layout Enumerate
+
+Se eliminaron alrededor de 50 artículos y 200 facturas.
+ El valor no es exacto, puesto que al ser pseudo-aleatoria la cantidad borrada
+ puede no ser 50 o 200.
+\layout Enumerate
+
+Se anotaron las estadísticas nuevamente.
+\layout Standard
+
+Ahora, los tamaños de bloque para los archivos con bloques fueron tomados
+ de 512 bytes, por ser una unidad típica de dispositivos de almacenamiento,
+ y nos pareció lógico dada la similitud utilizar esta unidad.
+\layout Standard
+
+De la operatorio antes descripta sale la siguiente tabla :
+\layout Standard
+
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+T1
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+
+Evidentemente para el caso de artículos, una muy mala eleccion seria utilizar
+ el archivo de tipo3, puesto que al usar registros constantes es posible
+ que se desperdicie mucho espacio si ocurren muchas eliminaciones (como
+ se observa en la tabla).
+ Entre los tipos 1 y 2 no existe mucha diferencia en los números, por lo
+ que la desición podriía ser tomada en base a los tiempos de acceso.
+ Tomando este criterio el T2 sería la mejor forma de almacenar los datos
+ para si lo más frecuente son lecturas, ya que al leer se puede obtener
+ el offset desde el principio del registro, mientras que en el tipo1 se
+ debe hacer una búsqueda secuencial sobre el bloque, y de ser éste último
+ muy grande el tiempo de acceso puede ser elevado.
+ Para operaciones que requiera muchas bajas de elementos el tipo 2 no sería
+ la mejor opción, puesto que la liberación es compleja, ya que cuando se
+ da de baja un registro se debe verificar si dicho espacio se solapa con
+ algún espacio libre actual, de manera de mantener espacios libres como
+ lo hacen los sistemas de archivo ext2, manteniendo la lista de los offsets
+ y tamaño de espacios libres, a fin de buscar el que mejor ajuste en caso
+ de una alta.
+\the_end