rhunt01
Well Known Member
We've had our AS400 for 6 years now and we've never performed an RGZPFM on our production database.
I'm under the impression that the running RGZPFM against my production DB library with no other parameters will remove deleted records from all members and place the members/files into contiguous sectors of my disks (thus making sequential I/O more likely). Is this correct?
Now, I'm curious about the keyed file parameter. 90% of my DBA activities are spent in the MS SQL Server arena so it sounds as if AS400 tables/files are by default heaps...and that the "keyed" parameter imitates clustered indexes in the MS SQL world. Is this about right?
If so, there are definite benefits to being able to specify the keyed file. Although, if I really had to speed up sort orders, I might just incorporate covering indexes sorted appropriately. At the same time, I'm most interested in the most current records being close together to each other on disk - which is basically happening with the heap according to batch insert order.
Anyway, with all my ramblings what I'm working toward here is the question:
"What is everyone else out there doing to reduce fragmentation, reduce non-sequential I/O, and protect the general health of their DASD?"
Thanks in advance.
Ryan
I'm under the impression that the running RGZPFM against my production DB library with no other parameters will remove deleted records from all members and place the members/files into contiguous sectors of my disks (thus making sequential I/O more likely). Is this correct?
Now, I'm curious about the keyed file parameter. 90% of my DBA activities are spent in the MS SQL Server arena so it sounds as if AS400 tables/files are by default heaps...and that the "keyed" parameter imitates clustered indexes in the MS SQL world. Is this about right?
If so, there are definite benefits to being able to specify the keyed file. Although, if I really had to speed up sort orders, I might just incorporate covering indexes sorted appropriately. At the same time, I'm most interested in the most current records being close together to each other on disk - which is basically happening with the heap according to batch insert order.
Anyway, with all my ramblings what I'm working toward here is the question:
"What is everyone else out there doing to reduce fragmentation, reduce non-sequential I/O, and protect the general health of their DASD?"
Thanks in advance.
Ryan