Increase database expansion size

[Jon Tai]

Currently, we configure GT.M databases to expand by 1024 blocks whenever they run out of space. Databases are configured with a 4k block size, so that means the database will grow 4MB at a time.

In a conversation with Bhaskar, he indicated that we should stay with a 4k block size, but increase the expansion size:

"In production it's common to set the expansion size to expand once a month or so (there's no real disadvantage to a large expansion size because disk space is lazily allocated by default - there is an option to allocate all of it on each expansion for anyone who wants to do it that way)."

By a very rough estimate, one of our busier sites grows at about 3GB a month, so we should increase the number of blocks the database expands by to 737280 (~2.8GB). While we're at it, we should probably set the initial database size to the same number of blocks (currently it's 1024 blocks).

Note that for demo/appliance systems with small disks, we probably want to keep the current numbers. Perhaps we can auto-detect disk size at database-creation-time?

[Jon Tai (jontai)]

The maximum extension count seems to be 65535, which translates to 256MB with a 4K block size.

[Jon Tai (jontai)]

Punting