Total latency stats "roll-over" after a while

[MadMatt]

Need to make the variable larger to prevent this:

Memcached Blocks read 1001 : Total Time: 11344331 (us) : Avg Time : 11332 (us)
Memcached Blocks read 717717 : Total Time: 42855898 (ms) : Avg Time : 5971 (us)
Memcahced Blocks set norm 1 1001 : Total Time: 127537 (us): Avg Time : 127 (us)
Memcached Blocks set norm 1 742742 : Total Time: 1039517 (ms): Avg Time : 139 (us)
Memcached Blocks read 1001 : Total Time: 10605507 (us) : Avg Time : 10594 (us)
Memcached Blocks read 718718 : Total Time: 12280 (ms) : Avg Time : 1 (us)
Memcahced Blocks set norm 1 1001 : Total Time: 63392 (us): Avg Time : 63 (us)
Memcached Blocks set norm 1 743743 : Total Time: 1040151 (ms): Avg Time : 139 (us)