|depending on the db used, and how you set it up it may have to grow itself to be able to store that data i.e. if you origionally set up the db for 3gb, and its taking up all 3 or has gotten bigger, any time you insert you'll have to wait on the database to go find another contiguous section of disc to put the new data on. on sql server 2k you can set the inital size and the growth rate as a percentage or fixed amount, we have a 1tb raid array so we can let it grow 1gb at a time, which lets it work for a while without needing new space. we also created the db several times larger than it was when we built the server, so it wouldnt need to grow for a long time. Contiguous disk space is your friend for data heavy applications, because if you can put all a table or tables together it will reduce seek time. also disabling the log file or setting the log file up to have a large amount of space could help too, if its logging the inserts then that file will get pretty big and have to go find more space for itself.
i've greatly sped up our db server and other databases by forcing it to clear the log file, and giving it quite abit of space for it since we regularly upload (insert, delete, update) over 500 million rows in a handful of tables. we upload them to a temp database on the main server then do compares to deteremin what needs to be added removed or changed, then run those queries, so we arent adding 500 million rows every few months, but we do have to mess with that much data, the inserts are ususally only 20 or 30 million, but it does run fairly fast(20 to 30 minutes at most including initial upload done with bcp) on the new machine. top end dell 5u 15k rpm sata2 drives..its sweet.
hopefully this was somewhat helpful
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