Linux 2.4 Kernel Tunings used in SPECweb99 results File System Tunings http://www.linuxhq.com/kernel/v2.4/doc/sysctl/fs.txt.html /proc/sys/fs/file-max Maximum number of file-handles that the Linux kernel allocates, hence this establishes the maximum number of files that the system can have open at one time. Default: 4096 Benchmark setting: 128000 IPv4 Tunings URL: http://www.linuxhq.com/kernel/v2.4/doc/networking/ip-sysctl.txt.html /proc/sys/net/core/rmem_max /proc/sys/net/core/rmem_default Default and maximum size of the Linux socket input queues. Larger queue sizes can lead to a reduced risk of delays, so long as one does have the extra memory for the increased queues readily available. Not all combinations of (older) kernels and (older) cards can properly handle larger queue sizes. Default: 65536 Benchmark setting: 1048576 /proc/sys/net/core/wmem_max /proc/sys/net/core/wmem_default Default and maximum size of the Linux socket output queues; this enables web servers to send more of a web page to the network stack in fewer system calls (ideally the entire web page in one call). Default: 65536 Benchmark setting: 1048576 /proc/sys/net/ipv4/ip_local_port_range Set the range of ports that can be used. [Note these values are subject to limitations within the 16bit field that IPv4 uses.] Ports can be used up by network connections in various connected and tear-down states. If/When no more ports are available, any attempt to open a new connect() will fail. Default: 32768 61000 Benchmark setting: 16384 65536 /proc/sys/net/ipv4/ip_forward Do we, or do we not, forward packets between different network interfaces on this system. Default: 0 Benchmark setting: 0 {we will not be forward any packets} /proc/sys/net/ipv4/tcp_sack Do we, or do we not, use the optional TCP selective acknowledgements. [Most useful on lossy, congested, long-delay, or other erratic networks] Default: 1 Benchmark setting: 0 {do not use selective acknowledgements} /proc/sys/net/ipv4/tcp_timestamps= 0 Do we, or do we not, use the RFC1323 TCP timestamps. [Most useful on lossy, congested, long-delay, or other erratic networks] Default: 1 Benchmark setting: 0 {do not generate timestamps} /proc/sys/net/ipv4/tcp_window_scaling Do we, or do we not, use the RFC1323 TCP window scaling. [Most useful on lossy, congested, long-delay, or other erratic networks] Default: 1 Benchmark setting: 0 {do not use selective acknowledgements} /proc/sys/net/ipv4/tcp_max_tw_buckets Maximal number of timewait sockets held by system simultaneously. [Web servers with very high hit rates can generate very large numbers of connections in the TIME_WAIT state, and SPECweb99 rules require the web servers to maintain this state for at least 60 seconds.] Benchmark setting: 2000000 VM Tunings URL: http://www.linuxhq.com/kernel/v2.4/doc/sysctl/vm.txt.html /proc/sys/vm/bdflush Tuning values for the bdflush kernel daemon (flushes dirty buffers). Parameter 1 is what percentage is dirty before daemon acts. Parameter 2 is the maximal number of buffers to flush at one time Parameter 3 is the number of buffers to add to the free list each time Parameter 4 is the number of dirty buffers before waking bdflush Parameter 5 is ignored Parameter 6 is time for normal buffer to age before flushing Parameter 7 is time for superblock to age before flushing Parameter 8 is ignored Parameter 9 is ignored Default: 40, 500, 64, 256, 15, 30*HZ, 5*HZ, 1884, 2 Benchmark setting: 100 5000 640 2560 150 30000 5000 1884 2