Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : QUANTUM -- Ignore unavailable to you. Want to Upgrade?

To: John Biddle who wrote (7337)	2/16/1998 3:34:00 PM
From: Gottfried	Read Replies (1) \| Respond to of 9124

John, >Is it also true that each head is read from in series, rather than in parallel? It seems that if they were read from in parallel the more heads the better.< To read from several heads in parallell (i.e. simultaneously) would require a read channel for each head. Again a question of cost. If data is arranged by cylinder (a grouping of tracks on different disks - all accessible without moving the actuator), then one head at a time can be read. While this does not require actuator movement, you still have to wait until the desired data comes by (latency). GM PS: In the olden days of 14 inch disk drives there was a feature called "fixed heads". This was a number of unmovable heads (restricted to just one track). Customers could put data there that had to be accessed quickly and often. There was no delay due to actuator access time, just head-to-head switching.