Our SQL server lives on a SAN. It contains dozens of OLTP databases, some with several tables containing over 1m records.
We have been running Ola Hallengren's index maintenance scripts weekly, and it runs for several hours each time. Based on the fragmentation threshold, the script will either reorganize or reindex an index. We have observed that during reindexing, the log files get huge which leads to an excessive consumption of bandwidth during the log shipping.
Your hard drives are shared with other servers that are also making drive requests at the same time, so the drives will always be jumping all over the place to get data. Defragging your indexes is just meaningless busy work.
Googling this question leads to varying opinions, most supported with arguments that seem too brief or weak. Our tentative plan is to adjust the fragmentation threshold in our maintenance script so that it reorganizes much more often than it reindexes.
What is the final verdict? Is it worthwhile to defrag SQL indexes on a SAN considering the burdens associated with running weekly maintenance jobs?