Re: Shocking: RF SCSI slower than HS SCSI???

[bazyar@netcom.com (Jawaid Bazyar)]

Soenke,

  yes, clearly, a large linear block read will thrash the RamFAST's
cache.  Just as a large linear block memory move will thrash the Zip-GS's
cache.
  
  More useful benchmarks are: boot time with and without accelerator,
time to copy many small files, time to boot GNO, etc. "Real-life"
applications.

  Doing large block transfers from disk will indeed cause problems for
the RamFAST, as it has to transfer from disk to card, then card to
memory.  But if the data you're looking for is in the cache, then
it's 1MB/sec period.  So, in more common situations, the RamFAST's
average throughput will be between 512K/sec and 1MB/sec. In ProDOS
8, it's almost always 1MB/sec :)

  If I ever get a chance to work on the RamFAST's firmware, an "easy"
fix would be to transfer large blocks that will obviously thrash the
cache straight from disk to Apple memory. This can be done with the
RamFAST's hardware.

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