From 43c5d05d8f0854f33dcecb6adfab0918dfe3fb36 Mon Sep 17 00:00:00 2001 From: alexliyu7352 Date: Sun, 27 Mar 2022 21:25:40 +0800 Subject: [PATCH] =?UTF-8?q?=E4=BD=BF=E7=94=A8clone=E6=9B=BF=E4=BB=A3fork?= =?UTF-8?q?=20(#1518)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 使用clone替代fork 因为fork子进程有时会导致提前写时复制, 进而影响性能. 而vfork又会引起父进程阻塞 所以使用clone来产生子进程运行ffmpeg --- server/Process.cpp | 107 ++++++++++++++++++++++++++++++++++++++------- server/Process.h | 1 + 2 files changed, 91 insertions(+), 17 deletions(-) diff --git a/server/Process.cpp b/server/Process.cpp index fa685b28..1c9d680b 100644 --- a/server/Process.cpp +++ b/server/Process.cpp @@ -27,9 +27,63 @@ #include "Util/uv_errno.h" #include "Poller/EventPoller.h" #include "Process.h" + +#define STACK_SIZE (8192*1024) using namespace toolkit; using namespace std; +#ifndef _WIN32 +typedef struct +{ + const char *cmd_path; + char **cmd_args; + const char *log_file; +} params_t; + + +static int /* Start function for cloned child */ +childFunc(params_t *params) +{ + //取消cpu亲和性设置，防止FFmpeg进程cpu占用率不能超过100%的问题 + setThreadAffinity(-1); + //子进程关闭core文件生成 + struct rlimit rlim = {0, 0}; + setrlimit(RLIMIT_CORE, &rlim); + //重定向shell日志至文件 + char log_path[strlen(params->log_file) + 20]; + memset(log_path,0,sizeof(log_path)); + if (strlen(params->log_file) <= 1) { + //未指定子进程日志文件时，重定向至/dev/null + snprintf(log_path, sizeof(log_path), "%s", "/dev/null"); + } else { + snprintf(log_path, sizeof(log_path), "%s.%d", params->log_file, getpid()); + } + auto fp = File::create_file(params->log_file, "ab"); + if (!fp) { + fprintf(stderr, "open log file %s failed:%d(%s)\r\n", log_path, get_uv_error(), get_uv_errmsg()); + } else { + auto log_fd = fileno(fp); + // dup to stdout and stderr. + if (dup2(log_fd, STDOUT_FILENO) < 0) { + fprintf(stderr, "dup2 stdout file %s failed:%d(%s)\r\n", log_path, get_uv_error(), get_uv_errmsg()); + } + if (dup2(log_fd, STDERR_FILENO) < 0) { + fprintf(stderr, "dup2 stderr file %s failed:%d(%s)\r\n", log_path, get_uv_error(), get_uv_errmsg()); + } + // 关闭日志文件 + ::fclose(fp); + } + fprintf(stderr, "\r\n\r\n#### pid=%d,cmd=%s%s #####\r\n\r\n", getpid(), params->cmd_path, *params->cmd_args); + + // TODO: execv or execvp + auto ret = execv(params->cmd_path, params->cmd_args); + if (ret < 0) { + fprintf(stderr, "clone process failed:%d(%s)\r\n", get_uv_error(), get_uv_errmsg()); + } + return ret; +} +#endif + void Process::run(const string &cmd, string &log_file_tmp) { kill(2000); #ifdef _WIN32 @@ -71,8 +125,34 @@ void Process::run(const string &cmd, string &log_file_tmp) { WarnL << "start child process fail: " << get_uv_errmsg(); } fclose(fp); +#elif ((defined(__linux) || defined(__linux__))) + _process_stack = malloc(STACK_SIZE); + auto params = split(cmd, " "); + // memory leak in child process, it's ok. + char **char_params = new char *[params.size() + 1]; + for (int i = 0; i < (int) params.size(); i++) { + std::string &p = params[i]; + char_params[i] = (char *) p.data(); + } + // EOF: NULL + char_params[params.size()] = NULL; + params_t cmd_params = {params[0].c_str(), char_params, log_file_tmp.c_str()}; + int clonePid = clone(reinterpret_cast(&childFunc), (char *)_process_stack + STACK_SIZE, CLONE_FS | SIGCHLD, (void *) (&cmd_params)); + delete[] char_params; + if (clonePid == -1) { + WarnL << "clone process failed:" << get_uv_errmsg(); + free(_process_stack); + throw std::runtime_error(StrPrinter << "fork child process failed,err:" << get_uv_errmsg()); + } + _pid = clonePid; + if(log_file_tmp.empty()) { + InfoL << "start child process " << _pid << ", log file:" << "/dev/null"; + }else { + InfoL << "start child process " << _pid << ", log file:" << log_file_tmp.c_str() << "." << _pid; + } + #else - _pid = fork(); + _pid = vfork(); if (_pid < 0) { throw std::runtime_error(StrPrinter << "fork child process failed,err:" << get_uv_errmsg()); } @@ -91,10 +171,10 @@ void Process::run(const string &cmd, string &log_file_tmp) { setrlimit(RLIMIT_CORE, &rlim); //在启动子进程时，暂时禁用SIGINT、SIGTERM信号 - signal(SIGINT, SIG_IGN); - signal(SIGTERM, SIG_IGN); - signal(SIGSEGV, SIG_IGN); - signal(SIGABRT, SIG_IGN); + signal(SIGINT, SIG_DFL); + signal(SIGTERM, SIG_DFL); + signal(SIGSEGV, SIG_DFL); + signal(SIGABRT, SIG_DFL); //重定向shell日志至文件 auto fp = File::create_file(log_file.data(), "ab"); @@ -114,18 +194,6 @@ void Process::run(const string &cmd, string &log_file_tmp) { } fprintf(stderr, "\r\n\r\n#### pid=%d,cmd=%s #####\r\n\r\n", getpid(), cmd.data()); -#ifndef ANDROID - //关闭父进程继承的fd - for (int i = 3; i < getdtablesize(); i++) { - ::close(i); - } -#else - //关闭父进程继承的fd - for (int i = 3; i < 1024; i++) { - ::close(i); - } -#endif - auto params = split(cmd, " "); // memory leak in child process, it's ok. char **charpv_params = new char *[params.size() + 1]; @@ -298,6 +366,11 @@ void Process::kill(int max_delay, bool force) { CloseHandle(_handle); _handle = nullptr; } +#elif ((defined(__linux) || defined(__linux__))) + if(_process_stack){ + free(_process_stack); + _process_stack = nullptr; + } #endif } diff --git a/server/Process.h b/server/Process.h index aaae3e74..cd0b2917 100644 --- a/server/Process.h +++ b/server/Process.h @@ -31,6 +31,7 @@ public: private: pid_t _pid = -1; void *_handle = nullptr; + void* _process_stack = nullptr; int _exit_code = 0; };