Tagged queueing

Chris Evans (chris@ferret.lmh.ox.ac.uk)
Wed, 8 May 1996 19:12:45 +0100 (BST)


I run the aic7xxx driver on kernel 1.3.98. Let me quote an extract from it:

* o Tagged queueing - this driver is capable of tagged queueing
* but I am unsure as to how well the higher level driver implements
* tagged queueing.

The define enabling this feature is commented out. Does the higher level
handle tagged queueing ok now? I'm not exactly sure what tagged queueing
is, but get the impression it would assist performance.

Also,

* o Commands per lun - If tagged queueing is enabled, then you
* may want to try increasing AIC7XXX_CMDS_PER_LUN to more
* than 2.

[....]

* For adapters limited to 4 SCBs, you may want to actually
* decrease the commands per lun to 1, if you often have more
* than 2 devices active at the same time.

And from bootup messages:

aic7xxx: Using 16 SCB's after checking for SCB memory.

I currently have one device on the bus, soon to be two... any useful
suggestions anyone?

Cheers,
Chris.