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> SHORT ANSWER: Segregating partitions reduces seek time. Period. > > LONG ANSWER: Reads and writes tend to be grouped within a partition. > For > example, if you're starting a program, you're going to be doing a lot > of > reads somewhere in the /usr partition. If the program uses temporary > files, > you're going to do a lot of reads & writes in the /tmp partition. If > you're > saving a file, you're going to be doing lots of writes to the /home > partition. Hence, since most disk accesses occur in groups within a > partition, preference should be giving to reducing seek time WITHIN a > partition, rather than reducing seek time BETWEEN partitions. keep in mind that only around half of the seek time is because of the partition! Taking an IBM 120GXP as an example: Average seek: 8.5ms Full stroke seek: 15.0ms Time to rotate disk one round: 1/(7200/60)*1000 = 8.3ms Then, the sector you're looking for, will, by average, be half a round away from where you are, and thus, giving the minimum average seek time 8.3/2 = 4.15ms or something like half the seek time. Concidering this, you may gain a maximum <= 50% gain in using smaller partitions. btw. anyone that knows the zone layout on IBM drives? roy - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | |||||||||
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