Minix Network Performance

I have been using the ttcp test program to measure network throughput on various systems over many years so when it came to testing the Ethernet driver for the Prisma, ttcp was was the first tool I reached for. Having ported it to Prisma Minix, I then moved it back to PC Minix and ran a series of test to compare the throughput for different CPUs and network cards. When 2.0.2 was released, I re-ran the tests to confirm that the network performance had significantly improved as compared to 2.0.0. The results are given below and the source for ttcp can be found in the downloads section.

I am a little disappointed that the Prisma is only marginally faster than a 386SX25, I would have expected a bigger difference. It could be that the Prisma is being slowed down by DRAM access, the docs I have say the 33MHz CPU runs with 4 wait states for DRAM whereas the 386SX system claims to run with 0 wait states. Alternatively, my Ethernet driver may simply be "in need of some improvement".

Notes:

• The WD8003 series are 8-bit cards and the WD8013 series are 16-bit cards. Both use shared memory for access to the data buffers.
• The Amd7990, more commonly known as the LANCE, is the on-board Ethernet controller on the Prisma. It has a 16-bit interface and uses DMA to transfer data to buffers in main memory.
• Timings are taken from my NetBSD 1.3 system, which was the other end of the connection for all tests except the 486 WD8013 running 2.0.2. For that test, the Amiga couldn't keep up so it was run with a Pentium Linux system.
• The timings for uClinux were taken from the same NetBSD system but it had been updated to 1.4.1 since the previous tests were run.