espen@well.UUCP (Peter Espen) (11/12/89)
The info in the following graph was generated by "SCSI Evaluator 1.01" and clearly shows the amount of performance degradation that takes place when my 80 Meg Quantum with the new ROMS is doing it's "exercise routines". The normal data was taken when the drive was acting normally, and the degraded data was generated while the new ROM routines were taking place. Remember that these exercise routines occur at random times, and can sometimes go for a long time. NICE "FIX", HUH!!! View the following graph using Monaco 9 point...... 20000 |####### | # # = NORMAL PERFORMANCE 18000 | # * = DEGRADED PERFORMANCE | # 16000 | # VERTICAL SCALE = KBITS/SEC | # 14000 | # HORIZ. SCALE = TRANSFER SIZE (K) | # 12000 | # | # 10000 | # | # 8000 | ############################## | 6000 | | 4000 | | 2000 | ****************************************** |*** |____________________________________________________ 10 15 20 25 30 35 40 45 50 55 60 Hope we can get a REAL fix from Apple and Quantum soon! Peter Espen (espen@well)
vallon@sbcs.sunysb.edu (Justin Vallon) (11/13/89)
In article <14527@well.UUCP> espen@well.UUCP (Peter Espen) writes: > > The info in the following graph was generated by "SCSI Evaluator 1.01" and >clearly shows the amount of performance degradation that takes place when >my 80 Meg Quantum with the new ROMS is doing it's "exercise routines". > The normal data was taken when the drive was acting normally, and the degraded >data was generated while the new ROM routines were taking place. Remember that >these exercise routines occur at random times, and can sometimes go for a >long time. NICE "FIX", HUH!!! > > > View the following graph using Monaco 9 point...... > [ Graph that shows normal & degraded performance. The normal performance ] [ starts at 20Mbits/sec, and slopes from 20M to 8M from 20Kbytes to 8K ] [ and 8M from 25- ] I'm curious. I am not doubting that this graph is correct, but I have a question. I thought that the SCSI chip maximum data transfer rate was about 1.4 Mb(ytes)/sec. That's about 11-12 Mbits/sec. How do you get 20Mbits/sec transfer? I have a Mac II. Do the IIx/cx/ci's have faster SCSI chips? Just wondering... -Justin vallon@sbcs.sunysb.edu