Diskcached wasn't designed to be a faster solution, just a simpler one when compaired to Memcached. However, from these benchmarks, it holds up will and even should provide slightly faster reads.
Warning: Tests do not pass and therefore this isn't expected to actaully work on ruby 1.8.7 at this point. I'm including the benchmarks for it as an academic excercise.
user system total real diskcached set 3.260000 5.630000 8.890000 ( 21.660488) memcached set 1.460000 1.280000 2.740000 ( 4.070615) diskcached get 1.800000 0.720000 2.520000 ( 2.541142) memcached get 1.160000 1.410000 2.570000 ( 3.609896)
user system total real diskcached set 17.740000 8.140000 25.880000 ( 59.677151) memcached set 13.840000 1.960000 15.800000 ( 18.235553) diskcached get 11.860000 1.100000 12.960000 ( 13.003900) memcached get 9.270000 1.880000 11.150000 ( 12.346795)
user system total real diskcached set 3.370000 4.980000 8.350000 ( 20.467971) memcached set 1.340000 1.300000 2.640000 ( 3.962354) diskcached get 1.570000 0.350000 1.920000 ( 1.939561) memcached get 1.330000 1.250000 2.580000 ( 3.604914)
user system total real diskcached set 21.460000 6.950000 28.410000 ( 58.982826) memcached set 16.510000 1.920000 18.430000 ( 20.862692) diskcached get 16.570000 0.690000 17.260000 ( 17.306181) memcached get 12.120000 1.630000 13.750000 ( 14.967464)
user system total real diskcached set 3.520000 5.220000 8.740000 ( 21.928190) memcached set 1.350000 1.480000 2.830000 ( 4.178223) diskcached get 1.830000 0.370000 2.200000 ( 2.215781) memcached get 1.570000 1.710000 3.280000 ( 4.662109)
user system total real diskcached set 20.670000 7.170000 27.840000 ( 59.877671) memcached set 15.310000 2.790000 18.100000 ( 21.132083) diskcached get 14.950000 0.700000 15.650000 ( 15.720669) memcached get 14.850000 1.840000 16.690000 ( 17.971276)