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 : Rambus (RMBS) - Eagle or Penguin -- Ignore unavailable to you. Want to Upgrade?

To: jim kelley who wrote (49071)	8/6/2000 5:51:18 PM
From: Dan3	Read Replies (1) \| Respond to of 93625

Re: Wrong....check your specs for burst rate. Jim, Burst rate is pretty much a synonym for the interface spec. It can have some relevance when considering data held in the on drive cache, but not much, since modern operating systems request read ahead data anyway. In other words, the critical next few bytes in a cluster that could have resided in the 256K to 2 meg read ahead cache on the drive will generally have been already requested by the OS, so it will be read off the disk at the maximum rate (less than 40MB/sec) then transferred as fast as possible (which is not limited by a 66MB/sec ATA-66 bus). There will be some cases where data can be pulled out of the on drive cache at speeds limited by the interface. But you have to remember that if the requirements are streaming data, then it won't be in the cache (because it's already being requested at a higher rate than the physical drive can deliver), so you are limited by direct I/O speeds. Where the data is in the cache, it will have to be a delayed request for a byte from a cluster in cache. It will happen, but not often. I am reminded by Ali Chen that he presented links to tests in which performance of the disk interface was isolated and that those tests show no difference whether the interface is 50% faster than the max disk data rate (ATA-66) or 120% faster than the max disk data rate (ATA-100). In the near future, ATA-100 will become relevant. Right now it isn't. Dan