From: Robert Love <rml@tech9.net> To: linux-kernel@vger.kernel.org Subject: Updated Linux kernel preemption patches Date: 26 Aug 2001 21:57:43 -0400 Cc: nigel@nrg.org Available at: http://tech9.net/rml/linux/patch-rml-2.4.9-preempt-kernel-1 http://tech9.net/rml/linux/patch-rml-2.4.8-ac12-preempt-kernel-1 for kernel 2.4.9 and 2.4.8-ac12, respectively. This is a straight update of Nigel Gamble's Linux kernel preemption patch from http://kpreempt.sourceforge.net, updated for the above kernels. Thus, this is Nigel's code -- I merely updated it. I am eager to see work done on the patch and to see what its future may be. If you are in any way interested in application latency or real-time support, I suggest you check this out. If you are just curious, its an interesting patch none-the-less. Some benchmarks: kernel 2.4.8-ac12 (nonpreempt): dbench 16: Throughput 12.9453 MB/sec (NB=16.1816 MB/sec 129.453 MBit/sec) dbench 1: Throughput 76.0099 MB/sec (NB=95.0123 MB/sec 760.099 MBit/sec) kernel compile (make dep clean bzImage): 7:35.51 (386.34s user, 23.41s system) kernel 2.4.8-ac12 with preemptible kernel patch: dbench 16: Throughput 13.3579 MB/sec (NB=16.6974 MB/sec 133.579 MBit/sec) dbench 1: Throughput 31.4971 MB/sec (NB=39.3714 MB/sec 314.971 MBit/sec) kernel compile (make dep clean bzImage): 7:23.26 (387.10s user, 23.42s system) The performance increase in kernel compile and dbench 16 is decent, but the decrease in dbench 1 is odd. I am curious what numbers others find. My "how does it feel" benchmark is that bandwidth seems similar while multitasking may be a tad smoother with the patch. -- Robert M. Love rml at ufl.edu rml at tech9.net - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/