Linux: 性能: sysctl vs echo vs直接使用fopen

本文主要是介绍Linux: 性能: sysctl vs echo vs直接使用fopen，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

简介

在实际的生产中，需要对系统参数做修改，有三种方式可以实现，一个是sysctl命令来修改，一个是使用echo 命令来写入，另一个是使用fopen/write接口函数来操作配置文件。
这个对比也是相当的明显，echo要比sysctl的轻便些；因为sysctl的依赖库更多，需要加载的so也就多。相对于echo，直接操作文件的方式更优。

ldd对比

<sec01-oam-a:root>/root:
# ldd /usr/sbin/sysctllinux-vdso.so.1 (0x00007ffc63dc7000)libprocps.so.7 => /lib64/libprocps.so.7 (0x00007f9e62fa2000)libsystemd.so.0 => /lib64/libsystemd.so.0 (0x00007f9e62c56000)libdl.so.2 => /lib64/libdl.so.2 (0x00007f9e62a52000)libc.so.6 => /lib64/libc.so.6 (0x00007f9e6268d000)librt.so.1 => /lib64/librt.so.1 (0x00007f9e62485000)liblzma.so.5 => /lib64/liblzma.so.5 (0x00007f9e6225e000)liblz4.so.1 => /lib64/liblz4.so.1 (0x00007f9e62041000)libcap.so.2 => /lib64/libcap.so.2 (0x00007f9e61e39000)libmount.so.1 => /lib64/libmount.so.1 (0x00007f9e61bdf000)libgcrypt.so.20 => /lib64/libgcrypt.so.20 (0x00007f9e618c1000)libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007f9e616a9000)libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f9e61489000)/lib64/ld-linux-x86-64.so.2 (0x00007f9e633d0000)libblkid.so.1 => /lib64/libblkid.so.1 (0x00007f9e61236000)libuuid.so.1 => /lib64/libuuid.so.1 (0x00007f9e6102e000)libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f9e60e03000)libgpg-error.so.0 => /lib64/libgpg-error.so.0 (0x00007f9e60be2000)libpcre2-8.so.0 => /lib64/libpcre2-8.so.0 (0x00007f9e6095e000)
<sec01-oam-a:root>/root:
# which echo
/usr/bin/echo
<sec01-oam-a:root>/root:
# ldd /usr/bin/echolinux-vdso.so.1 (0x00007ffccf9f0000)libc.so.6 => /lib64/libc.so.6 (0x00007f5d8b4c2000)/lib64/ld-linux-x86-64.so.2 (0x00007f5d8ba90000)

下面是sysctl的strace；

# /root/strace sysctl -w net.ipv4.conf.oam2.forwarding=1
execve("/usr/sbin/sysctl", ["sysctl", "-w", "net.ipv4.conf.oam2.forwarding=1"], 0x7ffc55a74680 /* 27 vars */) = 0
brk(NULL)                               = 0x55c5a9d04000
arch_prctl(0x3001 /* ARCH_??? */, 0x7fff46315090) = -1 EINVAL (Invalid argument)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=24207, ...}) = 0
mmap(NULL, 24207, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f2f1f2ca000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libprocps.so.7", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0M\0\0\0\0\0\0"..., 832) = 832
lseek(3, 69224, SEEK_SET)               = 69224
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=83312, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f2c8000
lseek(3, 69224, SEEK_SET)               = 69224
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2252824, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1ee7b000
mprotect(0x7f2f1ee8c000, 2097152, PROT_NONE) = 0
mmap(0x7f2f1f08c000, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x11000) = 0x7f2f1f08c000
mmap(0x7f2f1f08f000, 73752, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f08f000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libsystemd.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0p\235\1\0\0\0\0\0"..., 832) = 832
lseek(3, 1319560, SEEK_SET)             = 1319560
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=1387696, ...}) = 0
lseek(3, 1319560, SEEK_SET)             = 1319560
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 3453880, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1eb2f000
mprotect(0x7f2f1ec72000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1ee71000, 36864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x142000) = 0x7f2f1ee71000
mmap(0x7f2f1ee7a000, 952, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1ee7a000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0p\16\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=19128, ...}) = 0
mmap(NULL, 2109600, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1e92b000
mprotect(0x7f2f1e92e000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1eb2d000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f2f1eb2d000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0`\256\3\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2089936, ...}) = 0
lseek(3, 808, SEEK_SET)                 = 808
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 3950816, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1e566000
mprotect(0x7f2f1e722000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1e921000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1bb000) = 0x7f2f1e921000
mmap(0x7f2f1e927000, 14560, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1e927000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/librt.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0000$\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=42744, ...}) = 0
mmap(NULL, 2128832, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1e35e000
mprotect(0x7f2f1e365000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1e564000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6000) = 0x7f2f1e564000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/liblzma.so.5", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\3205\0\0\0\0\0\0"..., 832) = 832
lseek(3, 151120, SEEK_SET)              = 151120
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=162192, ...}) = 0
lseek(3, 151120, SEEK_SET)              = 151120
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2252808, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1e137000
mprotect(0x7f2f1e15c000, 2097152, PROT_NONE) = 0
mmap(0x7f2f1e35c000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x25000) = 0x7f2f1e35c000
mmap(0x7f2f1e35d000, 8, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1e35d000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/liblz4.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@$\0\0\0\0\0\0"..., 832) = 832
lseek(3, 112464, SEEK_SET)              = 112464
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=119760, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f2c6000
lseek(3, 112464, SEEK_SET)              = 112464
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2211848, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1df1a000
mprotect(0x7f2f1df36000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1e135000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1b000) = 0x7f2f1e135000
mmap(0x7f2f1e136000, 8, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1e136000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libcap.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\220&\0\0\0\0\0\0"..., 832) = 832
lseek(3, 26952, SEEK_SET)               = 26952
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=33752, ...}) = 0
lseek(3, 26952, SEEK_SET)               = 26952
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2126224, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1dd12000
mprotect(0x7f2f1dd19000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1df18000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6000) = 0x7f2f1df18000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libmount.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\260\352\0\0\0\0\0\0"..., 832) = 832
lseek(3, 348744, SEEK_SET)              = 348744
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=371384, ...}) = 0
lseek(3, 348744, SEEK_SET)              = 348744
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2462976, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1dab8000
mprotect(0x7f2f1db0e000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1dd0d000, 16384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x55000) = 0x7f2f1dd0d000
mmap(0x7f2f1dd11000, 1280, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1dd11000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libgcrypt.so.20", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\273\0\0\0\0\0\0"..., 832) = 832
lseek(3, 1143920, SEEK_SET)             = 1143920
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=1187328, ...}) = 0
lseek(3, 1143920, SEEK_SET)             = 1143920
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 3268552, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1d79a000
mprotect(0x7f2f1d8b2000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1dab1000, 28672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x117000) = 0x7f2f1dab1000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libgcc_s.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0.\0\0\0\0\0\0"..., 832) = 832
lseek(3, 92624, SEEK_SET)               = 92624
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=99664, ...}) = 0
lseek(3, 92624, SEEK_SET)               = 92624
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2192080, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1d582000
mprotect(0x7f2f1d599000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1d798000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x16000) = 0x7f2f1d798000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360n\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=149976, ...}) = 0
mmap(NULL, 2225344, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1d362000
mprotect(0x7f2f1d37d000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1d57c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1a000) = 0x7f2f1d57c000
mmap(0x7f2f1d57e000, 13504, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1d57e000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libblkid.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@\267\0\0\0\0\0\0"..., 832) = 832
lseek(3, 311944, SEEK_SET)              = 311944
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=343624, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f2c4000
lseek(3, 311944, SEEK_SET)              = 311944
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2434848, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1d10f000
mprotect(0x7f2f1d15c000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1d35b000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4c000) = 0x7f2f1d35b000
mmap(0x7f2f1d361000, 1824, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1d361000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libuuid.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\300\32\0\0\0\0\0\0"..., 832) = 832
lseek(3, 25296, SEEK_SET)               = 25296
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=33480, ...}) = 0
lseek(3, 25296, SEEK_SET)               = 25296
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2125856, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1cf07000
mprotect(0x7f2f1cf0e000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1d10d000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6000) = 0x7f2f1d10d000
mmap(0x7f2f1d10e000, 32, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1d10e000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libselinux.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\200z\0\0\0\0\0\0"..., 832) = 832
lseek(3, 157360, SEEK_SET)              = 157360
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=172104, ...}) = 0
lseek(3, 157360, SEEK_SET)              = 157360
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2270704, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1ccdc000
mprotect(0x7f2f1cd03000, 2097152, PROT_NONE) = 0
mmap(0x7f2f1cf03000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x27000) = 0x7f2f1cf03000
mmap(0x7f2f1cf05000, 5616, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f2f1cf05000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libgpg-error.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0PH\0\0\0\0\0\0"..., 832) = 832
lseek(3, 125832, SEEK_SET)              = 125832
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=144392, ...}) = 0
lseek(3, 125832, SEEK_SET)              = 125832
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2228800, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1cabb000
mprotect(0x7f2f1cada000, 2097152, PROT_NONE) = 0
mmap(0x7f2f1ccda000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1f000) = 0x7f2f1ccda000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libpcre2-8.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\200#\0\0\0\0\0\0"..., 832) = 832
lseek(3, 533040, SEEK_SET)              = 533040
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
fstat(3, {st_mode=S_IFREG|0755, st_size=543304, ...}) = 0
lseek(3, 533040, SEEK_SET)              = 533040
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 2634280, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f2f1c837000
mprotect(0x7f2f1c8ba000, 2093056, PROT_NONE) = 0
mmap(0x7f2f1cab9000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x82000) = 0x7f2f1cab9000
close(3)                                = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f2c2000
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f2f1f2bf000
arch_prctl(ARCH_SET_FS, 0x7f2f1f2bf940) = 0
mprotect(0x7f2f1e921000, 16384, PROT_READ) = 0
mprotect(0x7f2f1d57c000, 4096, PROT_READ) = 0
mprotect(0x7f2f1cab9000, 4096, PROT_READ) = 0
mprotect(0x7f2f1ccda000, 4096, PROT_READ) = 0
mprotect(0x7f2f1eb2d000, 4096, PROT_READ) = 0
mprotect(0x7f2f1cf03000, 4096, PROT_READ) = 0
mprotect(0x7f2f1d10d000, 4096, PROT_READ) = 0
mprotect(0x7f2f1d35b000, 20480, PROT_READ) = 0
mprotect(0x7f2f1d798000, 4096, PROT_READ) = 0
mprotect(0x7f2f1dab1000, 8192, PROT_READ) = 0
mprotect(0x7f2f1e564000, 4096, PROT_READ) = 0
mprotect(0x7f2f1dd0d000, 12288, PROT_READ) = 0
mprotect(0x7f2f1df18000, 4096, PROT_READ) = 0
mprotect(0x7f2f1e135000, 4096, PROT_READ) = 0
mprotect(0x7f2f1e35c000, 4096, PROT_READ) = 0
mprotect(0x7f2f1ee71000, 32768, PROT_READ) = 0
mprotect(0x7f2f1f08c000, 8192, PROT_READ) = 0
mprotect(0x55c5a8c7c000, 4096, PROT_READ) = 0
mprotect(0x7f2f1f2d0000, 4096, PROT_READ) = 0
munmap(0x7f2f1f2ca000, 24207)           = 0
set_tid_address(0x7f2f1f2bfc10)         = 1005130
set_robust_list(0x7f2f1f2bfc20, 24)     = 0
rt_sigaction(SIGRTMIN, {sa_handler=0x7f2f1d368970, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f2f1d374cf0}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {sa_handler=0x7f2f1d368a00, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f2f1d374cf0}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
getrandom("\x02\x56\x3e\xec\x56\xaa\x40\x97", 8, GRND_NONBLOCK) = 8
brk(NULL)                               = 0x55c5a9d04000
brk(0x55c5a9d25000)                     = 0x55c5a9d25000
statfs("/sys/fs/selinux", {f_type=SELINUX_MAGIC, f_bsize=4096, f_blocks=0, f_bfree=0, f_bavail=0, f_files=0, f_ffree=0, f_fsid={val=[0, 0]}, f_namelen=255, f_frsize=4096, f_flags=ST_VALID|ST_RELATIME}) = 0
statfs("/sys/fs/selinux", {f_type=SELINUX_MAGIC, f_bsize=4096, f_blocks=0, f_bfree=0, f_bavail=0, f_files=0, f_ffree=0, f_fsid={val=[0, 0]}, f_namelen=255, f_frsize=4096, f_flags=ST_VALID|ST_RELATIME}) = 0
access("/etc/selinux/config", F_OK)     = -1 ENOENT (No such file or directory)
access("/etc/system-fips", F_OK)        = -1 ENOENT (No such file or directory)
access("/etc/gcrypt/fips_enabled", F_OK) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/proc/sys/crypto/fips_enabled", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
read(3, "0\n", 1024)                    = 2
close(3)                                = 0
prctl(PR_CAPBSET_READ, CAP_MAC_OVERRIDE) = 1
prctl(PR_CAPBSET_READ, 0x30 /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x28 /* CAP_??? */) = 1
prctl(PR_CAPBSET_READ, 0x2c /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x2a /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x29 /* CAP_??? */) = -1 EINVAL (Invalid argument)
openat(AT_FDCWD, "/proc/self/auxv", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0400, st_size=0, ...}) = 0
read(3, "!\0\0\0\0\0\0\0\0\2603F\377\177\0\0003\0\0\0\0\0\0\0\360\6\0\0\0\0\0\0"..., 1024) = 336
close(3)                                = 0
openat(AT_FDCWD, "/proc/sys/kernel/osrelease", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
read(3, "4.18.0-513.11.1.el8_9.x86_64\n", 1024) = 29
close(3)                                = 0
openat(AT_FDCWD, "/sys/devices/system/cpu/online", O_RDONLY|O_CLOEXEC) = 3
read(3, "0-1\n", 8192)                  = 4
close(3)                                = 0
openat(AT_FDCWD, "/proc/self/auxv", O_RDONLY) = 3
fstat(3, {st_mode=S_IFREG|0400, st_size=0, ...}) = 0
read(3, "!\0\0\0\0\0\0\0\0\2603F\377\177\0\0003\0\0\0\0\0\0\0\360\6\0\0\0\0\0\0"..., 1024) = 336
close(3)                                = 0
stat("/proc/sys/net/ipv4/conf/oam2/forwarding", {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
openat(AT_FDCWD, "/proc/sys/net/ipv4/conf/oam2/forwarding", O_WRONLY|O_TRUNC) = 3
write(3, "1\n", 2)                      = 2
close(3)                                = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(0x88, 0x2), ...}) = 0
write(1, "net.ipv4.conf.oam2.forwarding = "..., 34net.ipv4.conf.oam2.forwarding = 1
) = 34
close(1)                                = 0
close(2)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

下面是echo的strace

<sec01-oam-a:root>/proc/sys/net/ipv4/conf/oam2:
# /root/strace echo 1 > forwarding
execve("/usr/bin/echo", ["echo", "1"], 0x7fff4224fe48 /* 27 vars */) = 0
brk(NULL)                               = 0x55c8e50b8000
arch_prctl(0x3001 /* ARCH_??? */, 0x7ffd56e37120) = -1 EINVAL (Invalid argument)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=24207, ...}) = 0
mmap(NULL, 24207, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f372727d000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0`\256\3\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2089936, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f372727b000
lseek(3, 808, SEEK_SET)                 = 808
read(3, "\4\0\0\0\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32) = 32
mmap(NULL, 3950816, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f3726c90000
mprotect(0x7f3726e4c000, 2093056, PROT_NONE) = 0
mmap(0x7f372704b000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1bb000) = 0x7f372704b000
mmap(0x7f3727051000, 14560, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f3727051000
close(3)                                = 0
arch_prctl(ARCH_SET_FS, 0x7f372727c540) = 0
mprotect(0x7f372704b000, 16384, PROT_READ) = 0
mprotect(0x55c8e3bd3000, 4096, PROT_READ) = 0
mprotect(0x7f3727283000, 4096, PROT_READ) = 0
munmap(0x7f372727d000, 24207)           = 0
getrandom("\x57\x18\x64\x5a\x85\x50\x8b\xf1", 8, GRND_NONBLOCK) = 8
brk(NULL)                               = 0x55c8e50b8000
brk(0x55c8e50d9000)                     = 0x55c8e50d9000
brk(NULL)                               = 0x55c8e50d9000
fstat(1, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
write(1, "1\n", 2)                      = 2
close(1)                                = 0
close(2)                                = 0
exit_group(0)                           = ?
+++ exited with 0 +++

直接使用fopen/write接口函数

实现配置文件的修改，这个方法在应用程序，非脚本语言里，速度更快。可以尝试。

这篇关于Linux: 性能: sysctl vs echo vs直接使用fopen的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！

---