Hi. The code logic palloc a CronTask structure array, but assigns it to a pointer of two-dimension array. So the space is subsequently used as a pointer array whose type is CronTask *, instead of a structure array. There is no error thrown yet because the size of a CronTask * pointer is much less than a CronTask structure, so only the front part of the whole allocated space is used and an out-of-bound will never happen. But it is actually no need to allocate so much memory that won't be used.