If you add more than 1GB then you'll add 16VLFs. In general, most transaction logs will only have 20 or 30 VLFs - even 50 could be reasonable depending on the total size of the transaction log. However, in many cases what happens is that excessive autogrowths can cause an excessive number of VLFs to be added - sometimes resulting in hundreds of VLFs. Having an excessive number of VLFs can negatively impact all transaction log related activities and you may even see degradation in performance when transaction log backups occur. To see how many VLFs you have solely look at the number of rows returned by DBCC LOGINFO. The number of rows returned equals the number of VLFs your transaction log file has. If you have more than 50, I would recommend fixing it and adjusting your autogrowth so that it doesn't occur as fequently. To get rid of all of the execessive VLFs, follow these easy steps to shrink off the fragmented chunk and add a new, clean chunk to your transaction log:
Kimberly L. Tripp: Improving *my* SQL skills through your questions! http://www.SQLskills.com/blogs/kimberly
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