cannot move data fast enough i want to achieve an overall throughput rate of around megabytes sec for very large data transfers around mb i have a quadra i have a nubus network card that can pump data in to mac memory at mb s using block mode transfers i have a high speed disk array no asynchronous pb calls that can achieve mb s let s say all transfers go from disk to buffer to network card it is not enough to first transfer all the data from the disk to buffer then transfer all the data from the buffer to card mb s then mb s result in an overall mb s too slow so i tried the following scheme for an n megabyte transfer step load the st mb from disk to buffer step asynch send st mb out card load the nd mb from disk to buffer step asynch send nd mb out card load the rd mb from disk to buffer step n asynch send the n mb out card load the nth mb from disk to buffer step n send the nth mb out card even though the code apparently does execute the card transfer asynchronously and the card does not use the mac cpu at all it is using the buffer tho each of the steps through n take as long as if the two transfers were executed one after another so there is no improvement in the rate why is the mac ram dual port so the nubus card and the disk driver can both access data at the same time is the problem that the two devices card and disk driver both have to use the same bus to mac ram is there anything i can do david david blume i get tired thinking of all the things i dcb wdl wdl loral com don t want to do bukowski barfly
