HI !

I'm very new to L4Linux so my question might be obvious - anyway did not find anything directly related in the archive. For a start I did a quick performance comparison using lmbench-3.0.

This comparison is based on the L4Linux-2.6 running a debina ramdisk lmbench-3.0 vs Linux-2.6.14 running from harddisk (though data files were in tempfs in both cases - so the HD should not really have much of an impact).

L4Linux Linux 2.6.14

com lat.: (us) lat_pipe 14.1-14.5 2.0 lat_fifo 13.9-14.6 2.2 lat_unix 19.4-19.5 3.2 lat_sem 3.5 0.6

lat_proc: (us) fork 805-1249 80-82 exec 3124-3784 212-230 shell 9992-9997 2480-2592

tlb: 7,8,32 always 32

bw com: (MB/s) bw_pipe 921-958 1338-1352 bw_unix 429-753 1122-1138

lat mem: oopses under L4Linux - no results

bw_mem: (MB/s) bcopy 3856-4066 5056-5080 rdwr 11937-13242 16052

syscall: (us) null 2.4-2.8 0.13 read 2.6-3.3 0.26-0.31 stat 4.4-4.9 0.89 open 6.5-8.1 1.16-1.39

The thing that supprises me is that the performance variation is much higher than on regular linux - in both cases the system was idle except for lmbench running, so I'm excluding any syslog parties or cron jobs fireing at inconvenient times (i.e bandwidth of UNIX sockets has a variance of almost 50% ?). Generally the performance difference is much larger than I would have expected, especially also in areas where I don't quite understand where the u-kenrel can impact the Linux system (i.e. bcopy, memory read-write)

Are these values in the usual range or did I screw up fundamentally ?

thx ! Prof. Nicholas Mc Guire University of Lanzhou Distributed & Embedded System Lab http://dslab.lzu.edu.cn School of Information Science and Engeneering mcguire@lzu.edu.cn Tianshui South Road 222. Lanzhou 730000 .P.R.China Tel:+86-931-8912025 Fax:+86-931-8912022 Lichtensteinstr. 31, Mistelbach A-2130 Austria Tel:+43-2572-201082 Fax:+43-2572-201084