ProcStats Class Reference

#include </builds/gaudi/Gaudi/GaudiAud/src/ProcStats.h>

Collaboration diagram for ProcStats:

Classes
class	unique_fd

Public Member Functions
	ProcStats ()
bool	fetch (procInfo &fill_me)
auto	pageSize () const noexcept

Static Public Member Functions
static ProcStats *	instance ()

Private Member Functions
void	open_ufd ()

Private Attributes
unique_fd	m_ufd
double	m_pg_size { 0 }
procInfo	m_curr
bool	m_valid { false }
std::mutex	m_mutex

Detailed Description

Definition at line 38 of file ProcStats.h.

Constructor & Destructor Documentation

ProcStats()

ProcStats::ProcStats ( )

inline

Definition at line 41 of file ProcStats.h.

{ open_ufd(); }

Member Function Documentation

fetch()

bool ProcStats::fetch

(

procInfo &

fill_me

)

Definition at line 259 of file ProcStats.cpp.

                                   {
  if ( !m_valid ) { return false; }
 
  std::scoped_lock lock{ m_mutex };
 
#if defined( __linux__ ) or defined( __APPLE__ )
 
  auto read_proc = [&]() {
    bool       ok = true;
    int        cnt{ 0 };
    char       buf[500];
    linux_proc pinfo;
    m_ufd.lseek( 0, SEEK_SET );
    if ( ( cnt = m_ufd.read( buf, sizeof( buf ) ) ) < 0 ) { ok = false; }
    if ( cnt > 0 ) {
      buf[std::min( static_cast<std::size_t>( cnt ), sizeof( buf ) - 1 )] = '\0';
      sscanf(
          buf,
          // 1  2  3  4  5  6  7  8  9  10  1   2   3   4   5   6   7   8   9   20  1   2   3   4   5   6   7   8   9
          // 30  1   2   3   4   5
          "%d %s %c %d %d %d %d %d %lu %lu %lu %lu %lu %lu %lu %ld %ld %ld %ld %ld %ld %llu %lu %ld %lu %lu %lu %lu "
          "%lu %lu %lu %lu %lu %lu %lu",
          &pinfo.pid, pinfo.comm, &pinfo.state, &pinfo.ppid, &pinfo.pgrp, &pinfo.session, &pinfo.tty, &pinfo.tpgid,
          &pinfo.flags, &pinfo.minflt, &pinfo.cminflt, &pinfo.majflt, &pinfo.cmajflt, &pinfo.utime, &pinfo.stime,
          &pinfo.cutime, &pinfo.cstime, &pinfo.priority, &pinfo.nice, &pinfo.num_threads, &pinfo.itrealvalue,
          &pinfo.starttime, &pinfo.vsize, &pinfo.rss, &pinfo.rlim, &pinfo.startcode, &pinfo.endcode, &pinfo.startstack,
          &pinfo.kstkesp, &pinfo.kstkeip, &pinfo.signal, &pinfo.blocked, &pinfo.sigignore, &pinfo.sigcatch,
          &pinfo.wchan );
      // resident set size in pages
      const auto       pr_size   = static_cast<double>( pinfo.vsize );
      const auto       pr_rssize = static_cast<double>( pinfo.rss );
      constexpr double MB        = 1.0 / ( 1024 * 1024 );
      f.vsize                    = pr_size * MB;
      f.rss                      = pr_rssize * m_pg_size * MB;
      if ( 0 == pinfo.vsize ) { ok = false; }
    }
    return ok;
  };
 
  // attempt to read from proc
  if ( !read_proc() ) {
    std::cerr << "ProcStats : -> Problems reading proc file. Will try reopening..." << std::endl;
    open_ufd();
    if ( !read_proc() ) { return false; }
  }
 
#else
  f.vsize = 0;
  f.rss   = 0;
  return false;
#endif // __linux__ or __APPLE__
 
  m_curr.rss   = f.rss;
  m_curr.vsize = f.vsize;
 
  return true;
}

instance()

ProcStats * ProcStats::instance ( )

static

Definition at line 239 of file ProcStats.cpp.

                               {
  static ProcStats inst{};
  return &inst;
}

open_ufd()

void ProcStats::open_ufd ( )

private

Definition at line 244 of file ProcStats.cpp.

                         {
  m_valid = false;
#if defined( __linux__ ) or defined( __APPLE__ )
  m_ufd.close();
  m_pg_size        = sysconf( _SC_PAGESIZE ); // getpagesize();
  const auto fname = "/proc/" + std::to_string( getpid() ) + "/stat";
  m_ufd.open( fname.c_str(), O_RDONLY );
  if ( !m_ufd ) {
    std::cerr << "ProcStats : Failed to open " << fname << std::endl;
  } else {
    m_valid = true;
  }
#endif // __linux__ or __APPLE__
}

pageSize()

auto ProcStats::pageSize ( ) const

inlinenoexcept

Definition at line 49 of file ProcStats.h.

{ return m_pg_size; }

Member Data Documentation

m_curr

procInfo ProcStats::m_curr

private

Definition at line 106 of file ProcStats.h.

m_mutex

std::mutex ProcStats::m_mutex

private

Definition at line 108 of file ProcStats.h.

m_pg_size

double ProcStats::m_pg_size { 0 }

private

Definition at line 105 of file ProcStats.h.

m_ufd

unique_fd ProcStats::m_ufd

private

Definition at line 104 of file ProcStats.h.

m_valid

bool ProcStats::m_valid { false }

private

Definition at line 107 of file ProcStats.h.

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The documentation for this class was generated from the following files:

• GaudiAud/src/ProcStats.h
• GaudiAud/src/ProcStats.cpp