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software | Windows | The Intel IA32 processors have a base pointer register called EBP . The EBP register is typically set to the value of the ESP register at the beginning of a procedure, and used to address the procedure arguments and locally allocated variables throughout the procedure. Thus, the arguments are located at …
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software | Windows | EDI: The Destination Index Every loop that generates data must store the result in memory, and doing so requires a moving pointer. The destination index, EDI, is that pointer. The destination index holds the implied write address of all string operations. The most useful string instruction, remarkably enough, is the seldom-used …
(gdb) info auxv 33 AT_SYSINFO_EHDR System-supplied DSO’s ELF header 0x7fff7a9ff000 16 AT_HWCAP Machine-dependent CPU capability hints 0x78bfbff 6 AT_PAGESZ System page size 4096 17 AT_CLKTCK Frequency of times() 100 3 AT_PHDR Program headers for program 0x400040 4 AT_PHENT Size of program header entry 56 5 AT_PHNUM Number of program headers 8 7 AT_BASE Base address …
(gdb) info auxv 33 AT_SYSINFO_EHDR System-supplied DSO’s ELF header 0x7fff7a9ff000 16 AT_HWCAP Machine-dependent CPU capability hints 0x78bfbff 6 AT_PAGESZ System page size 4096 17 AT_CLKTCK Frequency of times() 100 3 AT_PHDR Program headers for program 0x400040 4 AT_PHENT Size of program header entry 56 5 AT_PHNUM Number of program headers 8 7 AT_BASE Base address …
$cat /proc/sys/net/ipv4/tcp_reordering 3 $ tcp_reordering – INTEGER Maximal reordering of packets in a TCP stream. Default: 3 proj-rep/kernel_code/tcp_ipv4.c 1921: tp->reordering = sysctl_tcp_reordering; 1922: nms.csail.mit.edu/~kandula/data/tcp-mult.tgz – Unknown – C irestarter-0.9.0/src/netfilter-script.c 271: fprintf (script, “# Set TCP Re-Ordering value in kernel to ‘5’\n”); 272: fprintf (script, “if [ -e /proc/sys/net/ipv4/tcp_reordering ]; then\n” 273: ” echo 5 > …
$cat /proc/sys/net/ipv4/tcp_no_metrics_save 0 $ tcp_no_metrics_save Normally, TCP will remember some characteristics about the last connection in the flow cache. If tcp_no_metrics_save is set, then it doesn’t. Useful for benchmarks or other tests. net/ipv4/sysctl_net_ipv4.c – 24 identical 452: { 453: .procname = “tcp_no_metrics_save”, 454: .data = &sysctl_tcp_nometrics_save, github.com/github/linux-2.6.git – GPL – C – More from linux-2.6.git …
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$cat /proc/sys/net/ipv4/tcp_mtu_probing 0 $ tcp_mtu_probing – INTEGER Controls TCP Packetization-Layer Path MTU Discovery. Takes three values: 0 – Disabled 1 – Disabled by default, enabled when an ICMP black hole detected 2 – Always enabled, use initial MSS of tcp_base_mss. source : Linux kernel Documentation. 2.6.32 147: /* Black hole detection */ 148: tcp_mtu_probing(icsk, sk); …
$cat /proc/sys/net/ipv4/tcp_moderate_rcvbuf 1 $ tcp_moderate_rcvbuf – BOOLEAN If set, TCP performs receive buffer auto-tuning, attempting to automatically size the buffer (no greater than tcp_rmem[2]) to match the size required by the path for full throughput. Enabled by default. source : Linux kernel Documentation kernel ( 2.6.32 ) trunk/coverage/common/ServerSpecs.pm – 1 identical 278: 247 tcp_max_syn_backlog 1024 …
$cat /proc/sys/net/ipv4/tcp_mem 40704 54272 81408 $ tcp_mem vector of 3 INTEGERs: min, pressure, max min: below this number of pages TCP is not bothered about its memory appetite. pressure: when amount of memory allocated by TCP exceeds this number of pages, TCP moderates its memory consumption and enters memory pressure mode, which is exited when …
$cat /proc/sys/net/ipv4/tcp_max_tw_buckets 180000 $ tcp_max_tw_buckets Maximal number of timewait sockets held by system simultaneously. If this number is exceeded time-wait socket is immediately destroyed and warning is printed. This limit exists only to prevent simple DoS attacks, you _must_ not lower the limit artificially, but rather increase it (probably, after increasing installed memory), if network …