I am seeing a severe performance drop in 8xx_io/enet.c in some cases I can't explain. The cause of the performance drop is the 1.12.1.8 ChangeSet to enet.c. Changeset comments "Original comments: Fixed potential race condition in transmit routine. Eliminated erroneous "BSY can't happen" error message.
I believe this race condition is actualized under heavy load." The testcase is simple: NFS mount root fs on target. Do a "time cp big_file new_bigfile" to warm up. start a "ping -f <target IP> on the NFS server. Do a few more "time cp big_file new_bigfile" The last step takes about 10-20 seconds(big_file is 8356 KB) before the above change. After the change it takes about 1 minute. Can anyone confirm this behavior? Jocke http://ppc.bitkeeper.com:8080/linuxppc_2_4_devel/diffs/arch/ppc/8xx_io/enet.c at 1.12.1.8?nav=index.html|src/.|src/arch|src/arch/ppc|sr c/arch/ppc/8xx_io|hist/arch/ppc/8xx_io/enet.c ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
