cvs commit: src/sys/dev/ata ata-all.c ata-all.h ata-chipset.cata-dma.c ata-pci.c ata-pci.h

[Dag-Erling Smorgrav]

Nate Lawson <nate at root.org> writes:
> Tagged queuing is orthogonal to caching.  TQ allows multiple transactions
> to be passed to the drive, allowing it to order and aggregate the requests
> as it thinks best.  TQ can be done with no cache because all the drive is
> tracking is handles to transactions (typically 16 bit ids).  Think of it
> as more like a pipeline than a cache.

It can't be done without cache, because you can't queue and reorder
transactions without some sort of cache.

DES
-- 
Dag-Erling Smorgrav - des at ofug.org